DEFENSE 

ACQUISITIONS

Future Aerostat and 

Airship Investment 

Decisions Drive 

Oversight and 

Coordination Needs

Report to the Subcommittee on 

Emerging Threats and Capabilities, 

Committee on Armed Services, 

U.S. Senate

October 2012 

GAO-13-81

United States Government Accountability Office

GAO
United States Government Accountability Office

Highlights of GAO-13-81, a report to the 

Subcommittee on Emerging Threats and 

Capabilities, Committee on Armed Services, 

U.S. Senate 

October 2012 

DEFENSE ACQUISITIONS

Future Aerostat and Airship Investment Decisions 

Drive Oversight and Coordination Needs 

Why GAO Did This Study

Use of lighter-than-air platforms, such 

as aerostats, which are tethered to the 

ground, and airships, which are freeflying, could significantly improve U.S. 

ISR and communications capabilities, 

and move cargo more cheaply over 

long distances and to austere 

locations. DOD is spending about $1.3 

billion in fiscal year 2012 to develop 

and acquire numerous aerostats and 

airships. 

GAO was asked to determine (1) what 

key systems governmentwide are 

being developed and acquired, 

including funding, purpose, and status; 

(2) any technical challenges these key 

efforts may be facing; and (3) how 

effectively these key efforts are being 

overseen to ensure coordination, and 

identify any potential for duplication. To 

address these questions, GAO 

reviewed and analyzed documentation 

and interviewed a wide variety of DOD 

and civil agency officials. 

What GAO Recommends

GAO recommends that DOD take 

actions based on the extent of its 

future investments in this area: (1) if 

investments are curtailed, ensure it has 

insight into all current and planned 

efforts in the short term; (2) if 

investments increase significantly, 

include the efforts in strategic 

frameworks to ensure visibility and 

coordination, guide innovation, and 

prioritize investments; and (3) ensure 

the roles and responsibilities of the 

senior official responsible for the 

oversight and coordination of airshiprelated programs are defined. DOD 

concurred with the recommendations.

What GAO Found

GAO identified 15 key aerostat and airship efforts that were underway or had 

been initiated since 2007, and the Department of Defense (DOD) had or has 

primary responsibility for all of these efforts. None of the civil agency efforts met 

GAO’s criteria for a key effort. Most of the aerostat and airship efforts have been 

fielded or completed, and are intended to provide intelligence, surveillance, and 

reconnaissance (ISR) support. The estimated total funding of these efforts was 

almost $7 billion from fiscal years 2007 through 2012. However, funding 

estimates beyond fiscal year 2012 decline precipitously for aerostat and airship 

efforts under development, although there is an expectation that investment in 

the area will continue. 

Aerostat (left) and Airship (right)

Three of the four aerostat and airship efforts under development, plus another 

airship development effort that was terminated in June 2012, have suffered from 

high acquisition risks because of significant technical challenges, such as

overweight components, and difficulties with integration and software 

development, which, in turn, have driven up costs and delayed schedules. 

DOD has provided limited oversight to ensure coordination of its aerostat and 

airship development and acquisition efforts. Consequently, these efforts have not 

been effectively integrated into strategic frameworks, such as investment plans 

and roadmaps. At the time of GAO’s review, DOD did not have comprehensive 

information on all its efforts nor its entire investment in aerostats and airships.

Additionally, DOD’s coordination efforts have been limited to specific technical 

activities, as opposed to having a higher level authority to ensure coordination is 

effective. DOD has recently taken steps to bolster oversight, including the 

appointment of a senior official responsible for the oversight and coordination of 

airship-related programs. However, as of August 2012, DOD has not defined the 

details relating to the authority, scope, and responsibilities of this new position. 

Whether these steps are sufficient largely depends on the direction DOD intends 

to take with aerostat and airship programs. If it decides to continue investing in 

efforts, more steps may be needed to shape these investments. 

View GAO-13-81. For more information, 

contact Cristina Chaplain at (202) 512-4841 or 

chaplainc@gao.gov. 
Page i GAO-13-81 Defense Acquisitions

Letter 1 

Background 3

Most Key Aerostat and Airship Efforts Underway or Initiated Since 

2007 Have Been Fielded or Completed 8

Aerostat and Airship Efforts under Development Are Experiencing 

Technical Challenges 14

DOD Has Provided Limited Oversight to Ensure Coordination of Its 

Aerostat and Airship Efforts 19

Conclusions 25

Recommendations for Executive Action 26

Agency Comments and Our Evaluation 26

Appendix I Scope and Methodology 28

Appendix II Examples of Civil Government Use of Aerostats 30

Appendix III DOD Aerostat and Airship Development, Acquisition, and 

Operations Efforts 31

Appendix IV Funding Calculations for Aerostats and Airships, Fiscal Years 2007 

through 2016 37

Appendix V Comments from the Department of Defense 39

Appendix VI GAO Contact and Staff Acknowledgments 42

Tables

Table 1: Inventory of Aerostat and Airship Efforts as of June 2012 9

Table 2: Comparison of LEMV and Blue Devil Block 2 Capabilities 

as of June 2012 24

Table 3: Civil Government Agencies’ Aerostat Usage 30

Contents
Page ii GAO-13-81 Defense Acquisitions

Table 4: Aerostat and Airships Essentials, Purpose, and Status 31

Table 5: Total Aerostat Funding, Fiscal Years 2007 through 2016 37

Table 6: Total Airship Funding, Fiscal Years 2007 through 2016 38

Figures

Figure 1: Aerostat System (U.S. Army’s Persistent Threat Detection 

System) 4

Figure 2: Conventional Airship (U.S. Navy’s Advanced Airship 

Flying Laboratory) 5

Figure 3: Hybrid Airship (U.S. Army’s Long-Endurance MultiIntelligence Vehicle) 6

Figure 4: Funding for DOD Aerostat and Airship Efforts for Fiscal 

Years 2007 through 2012 11

Figure 5: Fiscal Years 2007 through 2016 Funding for Aerostats and 

Airships under Development 13
Page iii GAO-13-81 Defense Acquisitions

Abbreviations

AAFL Advanced Airship Flying Laboratory

DARPA Defense Advanced Research Projects Agency

DHS Department of Homeland Security

DOC Department of Commerce

DOD Department of Defense

DOE Department of Energy

EPA Environmental Protection Agency

FPDS-NG Federal Procurement Data System—Next Generation

FY fiscal year

GARP Geospatial Airship Research Platform

HALE-D High Altitude Endurance-Demonstrator

ISIS Integrated Sensor is Structure

ISR intelligence, surveillance, and reconnaissance

JLENS Joint Land Attack Cruise Missile Defense Elevated Netted 

Sensor

LEMV Long Endurance Multi-Intelligence Vehicle

LTA lighter-than-air

NASA National Aeronautics and Space Administration

NOAA National Oceanic and Atmospheric Administration

OASDR&E Office of the Assistant Secretary of Defense for Research 

and Engineering

O&M operations and maintenance

PGSS Persistent Ground Surveillance System

PSST Persistent Surveillance System-Tethered

PTDS Persistent Threat Detection System

RAID Rapid Aerostat Initial Deployment

RDT&E research, development, test, and evaluation

REAP Rapidly Elevated Aerostat Platform

TARS Tethered Aerostat Radar System

TRL technology readiness level

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Page 1 GAO-13-81 Defense Acquisitions

United States Government Accountability Office 

Washington, DC 20548

October 23, 2012

The Honorable Kay R. Hagan

Chairman

The Honorable Rob Portman

Ranking Member

Subcommittee on Emerging Threats and Capabilities

Committee on Armed Services

United States Senate

Platforms that utilize lighter-than-air (LTA) technologies—such as 

aerostats (buoyant craft tethered to the ground), and airships (buoyant 

craft that are free-flying)—may hold the potential for significantly 

increasing capabilities in the areas of persistent intelligence, surveillance, 

and reconnaissance (ISR) and communications, as well as lowering the 

costs of transporting cargo over long distances and to austere locations, 

such as those without aircraft runways.1

Because of the variety and number of aerostat and airship programs and 

interest in the extent of coordination across programs and potential for 

unnecessary duplication, you asked us to determine (1) what key aerostat 

and airship systems across the government are being developed and 

acquired, including funding, purpose, and status; (2) any technical 

challenges these key efforts may be facing; and (3) how effectively these 

key efforts are being overseen to ensure coordination, and identify any 

potential for duplication.

The Department of Defense 

(DOD) has embarked on a variety of efforts to develop and acquire LTA 

platforms for these purposes. DOD’s investments in these platforms 

totaled about $1.3 billion in fiscal year 2012. Additionally, other federal 

agencies, such as the Department of Homeland Security (DHS), are 

using or are considering using these platforms in conducting their 

missions. However, the visibility into and progress of these efforts, as well 

as how much they are being coordinated, has been unclear.

To determine what key aerostat and airship systems across the federal 

government are being developed and acquired, including funding, purpose, 

 

1

Persistence is the length of time a sensor can provide continuous coverage of a location, 

target, or activity of interest.

 
 

Page 2 GAO-13-81 Defense Acquisitions

and status of those systems, we reviewed documentation and interviewed 

officials on the status and progress of aerostat and airship development 

efforts in areas such as requirements, budgets, funding, costs, schedule, 

contracting, technology maturation, and actual or planned operational 

characteristics. In doing so, we developed an inventory of key airship and 

aerostat development and acquisition efforts which enabled a comparison 

of platform types, performance attributes, and costs. Based on funding data 

we collected, we determined that our definition of “key aerostat and airship 

systems being planned, developed, and acquired” includes two key criteria 

(1) total funding of $1 million or more for fiscal years 2007 to 2012, and (2) 

efforts to plan, develop, or acquire systems that include both a platform and 

payload (such as sensors or cargo) capability. We analyzed documentation 

and interviewed officials from various offices of the Secretary of Defense, 

Joint Chiefs of Staff, Army, Navy, and Air Force; U.S. Central Command; 

Defense Advanced Research Projects Agency; and Defense Logistics 

Agency. We also analyzed documentation and interviewed officials from 

civil agencies, including the Department of Homeland Security, Department 

of Energy, Environmental Protection Agency, National Oceanic and 

Atmospheric Administration, National Aeronautics and Space 

Administration, and Office of the Director of National Intelligence. We did 

not examine the development and utilization of LTA technologies outside of 

the federal government.

To identify any technical challenges these key aerostat and airship efforts 

may be facing, we analyzed documentation and interviewed officials from 

the organizations mentioned above. We used the collected information to 

assess any identified technical problems impacting the funding, cost, 

schedule, and performance of airships and aerostats.

To determine how the various key aerostat and airship efforts are being 

overseen to ensure coordination, and identify any potential for duplication, 

we assessed aerostat and airship investments, acquisitions, capabilities, 

and operations by analyzing documents and interviewing officials from the 

organizations listed above, analyzing the inventory of key efforts 

developed under our first objective, and reviewing prior GAO work for 

relevant criteria. Specifically, we assessed oversight at the programmatic 

and enterprise levels by reviewing organizational roles, responsibilities, 

and authorities as they relate to aerostat and airship development, 

acquisition, and operations efforts. We also determined the extent to 

which plans and planning activities integrated aerostat and airship 

development and acquisition efforts and capabilities within DOD. 

Reviewed plans and planning activities included architectures, roadmaps, 

investment plans, and requirements development. We also used the 
 

Page 3 GAO-13-81 Defense Acquisitions

information relating to various aspects of the development and acquisition 

efforts, such as requirements, and actual or planned performance 

attributes, to assess whether any of the efforts are potentially duplicative.

We conducted this performance audit from June 2011 to October 2012 in 

accordance with generally accepted government auditing standards. 

Those standards require that we plan and perform the audit to obtain 

sufficient, appropriate evidence to provide reasonable basis for findings 

and conclusions based on our audit objectives. We believe that the 

evidence obtained provides a reasonable basis for our findings and 

conclusions based on our audit objectives. Additional details on our scope 

and methodology are provided in appendix I.

This report examines two types of LTA platforms: aerostats and airships. 

Both use a lifting gas—most commonly helium—but an aerostat is tethered 

to the ground while an airship is free moving. Aerostats lack a propulsion 

mechanism and are connected to a mooring station on the ground by a 

long cable called a tether. The tether, in addition to securing the aerostat to 

one general area above the ground, usually provides power to the payload, 

such as ISR sensors and communications equipment, and carries data 

between the payload and ground control station. Airships, on the other 

hand, are manned or unmanned, self-propelled vehicles that have 

directional control. See figure 1 for an example of an aerostat system.

Background
 

Page 4 GAO-13-81 Defense Acquisitions

Figure 1: Aerostat System (U.S. Army’s Persistent Threat Detection System)

There are three basic types of airships: (1) non-rigid—which has no frame 

and maintains its envelope (external structure) shape through the slightly 

pressurized gas it contains; (2) semi-rigid—which also maintains its 

shape through the slightly pressurized gas it contains, but also has a 

structural keel along the bottom of the envelope to help distribute loads; 

and (3) rigid—which has an internal rigid frame to maintain its shape and 

to distribute lift and load weight. Blimps flying above sporting events are 

commonly non-rigid airships, whereas the Hindenburg airship of the 

1930s is an example of a rigid airship.

Airships can be further categorized by their shape—conventional or 

hybrid. A conventional airship has an ellipsoidal shape reminiscent of 

those that fly over sporting events. A hybrid airship combines the buoyant 

lift of a lighter-than-air gas with the aerodynamic lift created by the shape 

of the airship as it flies through the air. Shaped roughly like the crosssection of an aircraft wing, a hybrid airship can generate up to 30 percent 

of its lift as it flies. Additional lift can be generated by directing the thrust 

of on-board propulsion systems (called vectored thrust) downward. 

Because of the additional sources of lift, hybrid airships theoretically can 
 

Page 5 GAO-13-81 Defense Acquisitions

take off in a heavier-than-air configuration. See figures 2 and 3 for 

respective depictions of conventional and hybrid airships.

Figure 2: Conventional Airship (U.S. Navy’s Advanced Airship Flying Laboratory)
 

Page 6 GAO-13-81 Defense Acquisitions

Figure 3: Hybrid Airship (U.S. Army’s Long-Endurance Multi-Intelligence Vehicle)

In the early to mid 1900s, and especially during World War II, the U.S. 

Navy operated a variety of airships for maritime patrol and fleet 

reconnaissance, including assistance in antisubmarine warfare. 

Additionally, in the early 1930s, airships were used for commercial 

transportation across the Atlantic Ocean. However, advances in fixedwing aircraft design, capabilities, and availability, as well as in enemy 

antiaircraft weaponry, led to a marked decline in the military and 

commercial use of airships. For instance, the Navy disbanded its last 

airship unit in 1962, and since then, the military use of airships for other 

than research and development purposes essentially discontinued.
 

Page 7 GAO-13-81 Defense Acquisitions

Since 1978, DOD has operated aerostats along the southern U.S. border 

for counterdrug detection and monitoring. Additionally, civil government 

agencies have used aerostats for a variety of purposes, such as 

monitoring of environmental pollution, and atmospheric and climate 

research. For example, since 2009, the Environmental Protection Agency 

has used aerostats for the purpose of sampling air emissions from open 

sources, such as prescribed forest burns. Additionally, the Department of 

Commerce’s National Oceanic and Atmospheric Administration has used 

small aerostats to collect wind data. Furthermore, the Department of 

Homeland Security’s U.S. Customs and Border Protection is considering 

using aerostats for its border security mission. The overall investment of 

civil government agencies in LTA activities is small compared to that of 

DOD. See appendix II for examples of civil agency aerostat activities. 

While commercial use of airships has primarily been limited to sightseeing 

and advertising, there has been interest in using airships for cargo 

transportation to logistically austere locations, such as remote areas in 

Alaska and Canada.

Several factors have increased DOD’s attention toward LTA platforms. 

The lack of enemy air defense capabilities in recent military operations 

has made threats to LTA platforms appear to be low, and the military’s 

demand for persistent ISR has grown significantly. For example, DOD 

plans to almost double the number of aerostats—from 66 to 125—in 

Afghanistan for ISR in fiscal years 2011 and 2012. Also, growing budget 

pressures have encouraged the study of potential solutions to military 

problems, such as persistent ISR and heavy-lift cargo transportation, 

which may reduce procurement and operations and maintenance costs. 

For example, a 2008 Army Science Board study that compared fixed-wing 

unmanned aircraft, space satellites, and LTA platforms for providing 

persistent communications, surveillance, and reconnaissance missions, 

concluded that airships offered great promise at being effective in 

supporting these missions because of factors including ease of 

reconfigurability, extended time on station, large payload capacity, and 

lower cost.2

LTA platforms face several significant operational hazards. For example, 

weather phenomena such as high winds and lightning have posed the 

 

2

Department of the Army, Army Science Board FY2008 Summer Study Final Report: 

Platforms for Persistent Communications, Surveillance, and Reconnaissance, 

(Washington, D.C.: Sept. 2008).
 

Page 8 GAO-13-81 Defense Acquisitions

highest threats to aerostats deployed by the military in Afghanistan. 

Before the arrival of hazardous weather conditions, aerostat operations 

must cease and the platform must be lowered and secured to the mooring 

station to help prevent platform or payload damage. Additionally, high 

winds can make airships hard to control and increase fuel consumption, 

reducing on-station endurance. Furthermore, combat operations can 

result in punctures in the fabric caused by bullets and other projectiles. 

However, low helium pressure in the envelope (which is only slightly 

higher than the surrounding atmospheric pressure) means small helium 

leaks from bullet holes are typically slow and repairs can usually wait until 

a normally scheduled maintenance period.

We identified 15 key aerostat and airship efforts that were underway or 

had been initiated since 2007, and DOD had or has primary responsibility 

for all of these efforts.3 Most of these efforts have been fielded, 

completed, or terminated. Over the past 6 years, DOD’s overall 

investment has increased, and the estimated total funding of these efforts 

was almost $7 billion from fiscal years 2007 through 2012. However, 

funding estimates for aerostat and airship efforts under development 

beyond fiscal year 2012 decline significantly, although there is an 

expectation that investment in the area will continue.

Highlights on the 15 aerostat and airships efforts that were underway or 

initiated since 2007 by DOD are presented in the table below—details of 

each are provided in appendix III. Most of the aerostat and airship efforts 

have been fielded or completed, and are intended to provide ISR support 

or persistent surveillance, with on-station duration time typically greater 

than fixed-wing unmanned aircraft.

 

3

None of the civil agency efforts we identified (see appendix II) met our criteria for “key” 

systems being planned, developed, and acquired (details on our scope and methodology 

are provided in appendix I).

Most Key Aerostat 

and Airship Efforts 

Underway or Initiated 

Since 2007 Have Been 

Fielded or Completed

Status of 15 Efforts
 

Page 9 GAO-13-81 Defense Acquisitions

Table 1: Inventory of Aerostat and Airship Efforts as of June 2012

Name Purpose

Number 

of units

Total funding 

Fiscal years

2007-2012

(Millions of dollars) Status 

Fielded, completed, or terminated

Aerostats

Geospatial Airship Research 

Platform (GARP)

Test ISR and communication payloads 2 $9.4 Fielded

Persistent Ground Surveillance 

System (PGSS)

Provide ISR support 59 $1,508.0 Fielded

Persistent Threat Detection System 

(PTDS) 

Provide ISR support 66 $1,717.1 Fielded

Rapid Aerostat Initial Deployment 

(RAID)

Provide persistent surveillance for force 

protection

21 $127.1 Fielded

Rapidly Elevated Aerostat Platform 

(REAP)-XL B

Army: provide persistent surveillance/Navy: 

extended communications relay system

3 $5.3 Fielded

Tethered Aerostat Radar System 

(TARS) 

Support DOD’s counterdrug detection and 

monitoring mission along the southern U.S. 

border

8 $213.5 Fielded

Airships

Advanced Airship Flying Laboratory 

(AAFL, also known as MZ-3A)

Test ISR and communication payloads 1 $14.1 Fielded

Blue Devil Block 2 Demonstrate persistent multi-intelligence ISR 

capabilities

1 $243.6 Terminated

High Altitude EnduranceDemonstrator (HALE-D)Demonstrate ISR capabilities at high altitudes 1 $36.3 Completed

HiSentinel Demonstrate ISR capabilities at high altitudes 2 $11.2 Completed

Star Light Develop and demonstrate a high altitude and 

long endurance airship

1 $2.1 Terminated

Under development

Aerostat

Joint Land Attack Cruise Missile 

Defense Elevated Netted Sensor 

(JLENS) 

Provide detection and tracking of land-attack 

cruise missiles and other targets

2 $2,222.3 Under 

development

Airships

Integrated Sensor is Structure 

(ISIS) 

Develop and demonstrate radar sensor fully 

integrated into a stratospheric airship

1 $471.4 Under 

development

Long Endurance Multi-Intelligence 

Vehicle (LEMV)

Develop and demonstrate a hybrid prototype 

airship for long-endurance ISR support

1 $275.9 Under 

development

Project Pelican Develop and demonstrate a hybrid airship with 

a rigid internal structure and test airship 

buoyancy control technologies

1 $42.4 Under 

development

Source: GAO analysis of DOD data.
 

Page 10 GAO-13-81 Defense Acquisitions

DOD’s pursuit of aerostats and airships is mostly due to the ability of 

these platforms to loiter for a longer period of time than fixed-wing 

unmanned aircraft, which makes them very suitable for supporting the 

ISR mission. The various ISR sensors used or planned for the aerostats 

and airships in our review include:

• electro-optical cameras to conduct optical monitoring of the 

electromagnetic spectrum from ultraviolet through far infrared;

• ground moving target indicator radars to detect, locate, and track 

vehicles throughout a large area when they are moving slowly on or 

just above the surface of land or water;

• unattended transient acoustic measurement and signature intelligence 

systems that use sets of microphones to capture sounds that are 

processed and analyzed to determine the direction of the points of 

origin and impact of mortar launch; and

• signals intelligence sensors to collect transmissions deriving from 

communications, electronic, and foreign instrumentation systems.

The aerostat and airship efforts we identified vary in terms of the time 

they can operate on station in any single session. Their on-station 

endurance time is typically greater than that of fixed-wing unmanned 

aircraft. For example, the TARS aerostat is expected to stay on station for 

6 days, whereas the LEMV airship is expected to stay on station for at 

least 16 days. In contrast, tactical and theater-level fixed-wing unmanned 

aircraft can stay on station from 6 hours for a Shadow aircraft, to 40 hours 

for a Sky Warrior.4 The amount of time on station is greatly dependent on 

how often the aerostats and airships need to be topped off with additional 

helium, and in the case of most airships, how often they have to be 

refueled.5

 

4

See GAO, Defense Acquisitions: Opportunities Exist to Achieve Greater Commonality 

and Efficiencies among Unmanned Aircraft Systems, GAO-09-520 (Washington, D.C.: 

July 30, 2009).

5

The ISIS airship is to be solar-powered; therefore, the airship’s on-station endurance time 

is expected be one year. Also, the TARS aerostats are powered by a generator on board 

that must be refueled after 6 days of operations. 
 

Page 11 GAO-13-81 Defense Acquisitions

Over the past 6 years, overall total DOD investment in aerostat and 

airship development, acquisition, and operations and maintenance has 

increased, ranging from about $339 million in fiscal year 2007 to a high of 

about $2.2 billion in fiscal year 2010, and about $1.3 billion in fiscal year 

2012, as illustrated in figure 4. DOD has invested almost $7 billion from 

fiscal years 2007 through 2012 on key aerostat and airship efforts in our 

review. Moreover, aerostat-related investment—$5.8 billion—accounted 

for more than 80 percent of the total. See appendix IV for additional 

details on the reported funding for these efforts.

Figure 4: Funding for DOD Aerostat and Airship Efforts for Fiscal Years 2007 

through 2012

Note: Includes research, development, test, and evaluation; procurement; military construction; and 

operations and maintenance funding, as applicable, during fiscal years 2007 through 2012. See 

appendix IV for specific funding types and amounts. 

Over 90 percent of all estimated aerostat investment from fiscal years 2007 

to 2012—almost $5.4 billion—is attributed to the development and 

procurement of three aerostat programs—JLENS, PGSS, and PTDS. 

Aerostat funding increased through fiscal year 2010 primarily because of 

increased demand for PGSS and PTDS aerostats in Afghanistan and Iraq.

DOD Has Invested Almost 

$7 Billion in Aerostats and 

Airships over the Past 6 

Years
 

Page 12 GAO-13-81 Defense Acquisitions

Most of the total estimated airship investment from fiscal years 2007 to 

2012—approximately $1.1 billion—consists of research, development, 

test, and evaluation (RDT&E) costs. Of this amount, over 90 percent of 

the airship RDT&E investment—approximately $1 billion—is for the Blue 

Devil Block 2, ISIS and LEMV development efforts. The major increase 

depicted for fiscal year 2010 reflects an increase in RDT&E investment 

due to the beginning of funding for the Blue Devil Block 2 and LEMV 

development efforts, as well as a substantial increase for the ISIS 

development effort the Air Force began funding. 

Estimated funding for JLENS, ISIS, LEMV, and Project Pelican—efforts 

under development—is expected to decline significantly after fiscal year 

2012, as illustrated in figure 5.

Estimated Funding for 

Aerostats and Airships 

under Development 

Expected to Decline after 

Fiscal Year 2012 
 

Page 13 GAO-13-81 Defense Acquisitions

Figure 5: Fiscal Years 2007 through 2016 Funding for Aerostats and Airships under 

Development

Note: Includes research, development, test, and evaluation; procurement; and military construction 

funding, as applicable, during fiscal years 2007 through 2016. See appendix IV for specific funding 

types and amounts. 

However, according to DOD officials, investment in this area is expected 

to continue in the future. The aggregate funding for these four 

development efforts declines from $473 million in fiscal year 2012, to $23 

million in fiscal year 2016. Funding for JLENS, the development effort 

with the highest estimated cost from fiscal years 2012 to 2016, drops from 

$369 million in fiscal year 2012 to $187 million in fiscal year 2013, $92 

million in fiscal year 2014, $31 million in fiscal year 2015, and $23 million 

in fiscal year 2016. The original funding profile for JLENS showed 

substantively higher amounts over this time period, but due to a recent 

decision to reduce the number of JLENS aerostats that DOD intends to 

procure from 16 to 2, the current funding profile reflects this significant 

reduction in procurement. There are also investment uncertainties in the 

near term for LEMV and ISIS. According to LEMV program officials, if the 
 

Page 14 GAO-13-81 Defense Acquisitions

first LEMV is successfully demonstrated in Afghanistan, then it may 

transition to an acquisition program which would likely require additional 

funding. Also, ISIS program officials do not yet know if ISIS will become a 

program of record.

According to an official in the Office of the Under Secretary of Defense for 

Intelligence, while DOD expects to continue funding airship and aerostat 

efforts beyond fiscal year 2016, specific information regarding funding 

amounts is not available at this time. Furthermore, we did not find any 

current architectures, investment plans, or roadmaps that incorporated 

aerostat and airship efforts to indicate DOD’s commitment to increase or 

reduce its investment in this area.

Three of the four aerostat and airship efforts under development, plus 

another airship development effort that was terminated in June 2012, 

have suffered from high acquisition risks because of significant technical 

challenges, leading to cost overruns and schedule delays. Additionally, 

DOD used the rapid acquisition process to acquire airships that had high 

technical risks.

JLENS has experienced schedule delays and a Nunn-McCurdy unit cost 

breach,6

• The Army initiated JLENS system development in August 2005. 

JLENS consists of two large aerostats—over 240 feet in length—each 

with a 7,000 pound payload capacity for cruise missile detection and 

tracking. As we have previously reported, the program has 

 ISIS will not and LEMV did not meet their originally scheduled 

launch dates and have experienced cost overruns, and Blue Devil Block 2 

was terminated to avoid substantially increasing costs caused by 

technical problems.

 

6

Enacted in 1982, the Nunn-McCurdy statutory provision requires DOD to notify Congress 

whenever a major defense acquisition program’s unit cost experiences cost growth that 

exceeds certain thresholds. A breach of the critical cost growth threshold occurs when the 

program acquisition unit cost or the procurement unit cost increases by at least 25 percent 

over the current baseline estimate or at least 50 percent over the original baseline 

estimate.

Aerostat and Airship 

Efforts under 

Development Are 

Experiencing 

Technical Challenges

Aerostat and Airship 

Technical Challenges
 

Page 15 GAO-13-81 Defense Acquisitions

experienced design issues associated with the mobile mooring 

transport vehicle, as well as schedule delays caused by 

synchronization of JLENS with the Army’s Integrated Air and Missile 

Defense program.7

• ISIS is a joint Defense Advanced Research Projects Agency (DARPA) 

and Air Force science and technology effort initiated by DARPA in 

2004. ISIS is to develop and demonstrate a radar sensor system that 

is fully integrated into a stratospheric airship measuring 510 feet in 

length and with a payload capacity of 6,600 pounds. ISIS has 

experienced technical challenges stemming from subsystem 

development and radar antennae panel manufacturing. Consequently, 

earlier this year DARPA temporarily delayed airframe development 

activities, and instead will mainly focus on radar risk reduction 

activities. During this time period, the ISIS team will develop an airship 

risk reduction plan and conduct limited airship activities. Based on the 

radar and airship risk reduction studies, DARPA will reassess the 

future plan for ISIS with the Air Force.

JLENS was originally scheduled to enter 

production in September 2010. However, that same month, an 

aerostat accident resulted in the loss of one of the JLENS platforms. 

The accident, as well as recent system integration challenges, led to a 

decision to not procure production units. JLENS also incurred a critical 

Nunn-McCurdy program acquisition unit cost breach with the 

submission of the fiscal year 2013 President’s Budget due to a 100 

percent reduction in planned procurement quantities—the program 

previously planned to procure 16 aerostats. Now, the program is

scheduled to only acquire 2 aerostats using research and 

development funding, and is not expected to enter the production 

phase.

• The Army initiated development efforts on LEMV in 2010. At over 300 

feet in length and with a goal of carrying a 2,500 pound payload, LEMV 

offers substantive potential ISR capabilities—if the program can meet 

its performance objectives. LEMV’s deployment is behind schedule by 

at least 10 months (about a 56 percent schedule increase) due to 

 

7

The Army’s Integrated Air and Missile Defense program is being developed to connect 

sensors, weapons, and a common battle command system across an integrated fire 

control network to support the engagement of air and missile threats. See GAO, Defense 

Acquisitions: Assessments of Selected Weapon Programs, GAO-09-326SP (Washington, 

D.C.: Mar. 30, 2009); and Defense Acquisitions: Assessments of Selected Weapon 

Programs, GAO-11-233SP (Washington, D.C.: Mar. 29, 2011).
 

Page 16 GAO-13-81 Defense Acquisitions

issues with fabric production, getting foreign parts cleared through 

customs, adverse weather conditions causing the evacuation of work 

crews, and first-time integration and testing issues. Also, LEMV is about 

12,000 pounds overweight because components, such as tail fins, 

exceed weight thresholds. According to program officials, the increased 

weight reduces the airship’s estimated on-station endurance at an 

altitude of 20,000 feet from the required 21 days, to 4 to 5 days. 

However, current plans call for operating the airship at a lower altitude 

of 16,000 feet, which is expected to enable an on-station duration time 

of 16 days with minimal impacts to operational effectiveness (other than 

about a 24 percent reduction to on-station endurance). According to 

program officials, the biggest risk to program development was the 

ambitious 18-month initial development schedule (from June 2010 to 

December 2011). The Army successfully launched and recovered 

LEMV during its first flight in August 2012. The Army identified a fiscal 

year 2012 funding shortfall of $21.3 million resulting from the need for 

additional engineering and production support to mitigate and resolve 

technical issues at the LEMV assembly facility.

• The Air Force initiated development efforts on Blue Devil Block 2 in 

2010. Much like LEMV, this effort was to deliver a large airship that 

would carry a 2,500 pound payload in support of the ISR mission. The 

length of the airship was 370 feet. Prior to its termination in June 

2012, the Blue Devil Block 2 airship effort experienced significant 

technical problems resulting in cost overruns and schedule delays. 

According to an Air Force official, the Blue Devil Block 2 development 

effort had a very aggressive development schedule because it was 

intended to meet an urgent need for use in Afghanistan. Some of the 

technical problems included the tail fins, which were overweight and 

failed structural load design testing, rendering the airship not flyable. 

Other technical problems included the flight control software which 

experienced problems due to issues related to scaling—although the 

software worked well with a much smaller scale version of the airship, 

it did not work well with the much larger Blue Devil Block 2 airship. 

The Air Force terminated the Blue Devil Block 2 airship effort in June 

2012 due to the technical problems experienced with the airframe and 

the need to avoid substantially increasing costs of the effort. For 

example, the contractor estimated that the 1-year post-deployment 

operations and maintenance costs would total $29 million, but the Air 

Force’s cost estimate ranged between $100 and $120 million—an 

estimate that was at least 245 percent higher than the contractor’s 

estimate. According to an Air Force official, the contractor’s estimate 

did not include costs such as for spare parts and repairs.
 

Page 17 GAO-13-81 Defense Acquisitions

We found that DOD used its rapid acquisition process to initiate two airship 

efforts to quickly deliver warfighter capabilities, but significantly 

underestimated the risks of meeting cost, schedule, and performance 

goals.8 DOD has taken a number of steps to provide urgently needed 

capabilities to the warfighter more quickly and to alleviate the challenges 

associated with the traditional acquisition process for acquiring 

capabilities.9

• The LEMV acquisition strategy was initially approved when 

technologies were estimated to be at technology readiness levels 4 

through 7. At the time, DOD’s acquisition guidance recommended a 

technology readiness level 6 for product development.

Some of these steps include quicker requirements validation 

and reduced levels of oversight, including exemption from disciplined 

analyses that help to ensure requirements are achievable within available 

technologies, design, and other resources, and that programs have 

adequate knowledge in hand before moving forward in the acquisition 

process. The success of this accelerated acquisition process is predicated 

on efforts that do not involve high development and acquisition risks, such 

as limiting technology development by using mature technologies. 

However, in the case of LEMV and Blue Devil Block 2, the risks of these 

acquisitions were higher than usual for rapid acquisitions. Specifically:

10

 

8

Section 804(b) of the Ike Skelton National Defense Authorization Act for Fiscal Year 

2011, Pub. L. No. 111-383, requires, among other things, the acquisition process the 

Secretary of Defense develops for the fielding of urgent capabilities to be appropriate only 

for capabilities that can be fielded within a 2-24 month period.

DOD officials 

stated that they were willing to assume higher risk with the potential of 

9

DOD’s framework for planning, executing, and funding its weapon programs relies on 

three decision-making systems—the Defense Acquisition System that relies on DOD 

Instruction 5000.02, Operation of the Defense Acquisition System (Dec. 8, 2008), to guide 

and manage the development and procurement of major weapon capabilities; the Joint 

Capabilities Integration and Development System to assess gaps and recommend 

solutions; and the Planning, Programming, Budgeting, and Execution process to allocate 

funding resources—all of which involve lengthy time frames, large budgets, and 

development efforts that can take decades to procure weapon systems.

10DOD uses technology readiness levels (TRL) as a tool to assess technology maturity. 

TRLs are measured on a scale from 1 to 9, beginning with paper studies of a technology’s 

feasibility (TRL 1) and culminating with application of the technology in its final form and 

under mission conditions (TRL 9). Demonstration that pieces will work together in a test 

laboratory is TRL 4 and demonstrating that pieces work together in a simulated 

environment is TRL 5. Testing of a prototype system in a relevant environment is TRL 6 

and a major step up from TRL 6 is demonstrating an actual system prototype in a realistic 

environment, which is TRL 7. Our best practices work has shown that TRL 7 is the level of 

technology maturity that constitutes low risk for starting a product development program. 

Some Rapid Acquisitions 

Took on Too Much Risk
 

Page 18 GAO-13-81 Defense Acquisitions

developing an asset that had much greater on-station endurance and 

could provide capabilities on a single platform rather than on multiple 

aircraft. They stated that the higher risk of the effort was justified 

because there were multiple other efforts that were already providing 

surveillance capabilities in theater. DOD officials stated that, at the 

time the LEMV initiative was started, they expected the airship could 

be scaled up from a commercially existing demonstration variant and 

that the Army could meet the 18 month schedule to design, fabricate, 

assemble, test, and deploy the system. However, as noted earlier, 

LEMV experienced schedule delays of at least 10 months, largely 

rooted in technical, design, and engineering problems in scaling up 

the airship to the Army’s needs.

• DOD also significantly underestimated the risk of the Blue Devil Block 

2 development effort. The Secretary of Defense designated Blue Devil 

Block 2 as an urgent need solution to eliminate combat capability 

deficiencies that had resulted in combat fatalities. According to 

program officials, it was thought that the Blue Devil Block 2 airship 

would be a variant of commercially-available conventional airships 

and therefore deemed the technologies associated with the platform 

to be mature. However, the part of the program considered to be the 

lowest risk—the airship platform—turned out to be a high risk 

development effort. At the time of project cancelation, the Blue Devil 

Block 2 airship was more than 10,000 pounds overweight, which 

limited the airship’s estimated endurance. The weight issue 

contributed to other design concerns, the tail fins were too heavy and 

were damaged during testing, and the flight control software 

experienced problems related to scaling to a larger airship. The Air 

Force terminated the acquisition in June 2012.

The experience of these two programs under the urgent needs acquisition 

process is not unique. We recently reported that urgent needs initiatives 

that required technology development took longer after contract award to 

field because of technical challenges and testing delays than initiatives 

that involved mature technologies.11

 

11GAO, Urgent Warfighter Needs: Opportunities Exist to Expedite Development and 

Fielding of Joint Capabilities, 

Additionally, as reported in a 2009 

Defense Science Board Task Force Study, squeezing new technology 

GAO-12-385 (Washington, D.C.: Apr. 24, 2012).
 

Page 19 GAO-13-81 Defense Acquisitions

development into an urgent timeframe creates risks for delays and 

ultimately may not adequately address an existing capability gap.12

DOD has not provided effective oversight to ensure coordination of its 

aerostat and airship development and acquisition efforts. Consequently, 

these efforts have not been effectively integrated into strategic 

frameworks, such as investment plans and roadmaps. At the time of our 

review, DOD did not have comprehensive information on all its efforts nor 

its entire investment in aerostats and airships. Additionally, DOD’s 

coordination efforts have been limited to specific technical activities, as 

opposed to having a higher level authority to ensure coordination is 

effective. These shortcomings may have led to an instance of duplication, 

which ended when one airship effort was terminated. DOD has recently 

taken steps to bolster oversight. Whether these steps are sufficient 

largely depends on the direction DOD intends to take with aerostat and 

airship programs. If it decides to make significant future investments in 

efforts, more steps may be needed to shape these investments.

We have reported on the value of strategic planning for laying out goals 

and objectives, suggesting actions for addressing those objectives, 

allocating resources, identifying roles and responsibilities, and integrating 

relevant parties.13

 

12Report of the Defense Science Board Task Force on the Fulfillment of Urgent 

Operational Needs, July 2009.

However, DOD has not effectively integrated aerostat 

and airship capabilities into its strategic frameworks for future acquisitions 

of unmanned or ISR systems. At the time of our review, DOD did not 

have a reliable inventory of its aerostat and airship efforts, including

insight into its entire investment in aerostats and airships, or an office that 

could discuss the status of all of these efforts. We found several 

instances where aerostat and airship efforts were not well integrated into 

recent strategic planning documents, such as investment plans and 

13GAO, Defense Space Activities: National Security Space Strategy Needed to Guide 

Future DOD Space Efforts, GAO-08-431R (Washington, D.C.: Mar. 27, 2008); and 

Unmanned Aerial Vehicles: Improved Strategic and Acquisition Planning Can Help 

Address Emerging Challenges, GAO-05-395T (Washington, D.C.: Mar. 9, 2005).

DOD Has Provided 

Limited Oversight to 

Ensure Coordination 

of Its Aerostat and 

Airship Efforts

Aerostat and Airship 

Capabilities Not 

Effectively Integrated into 

Strategic Frameworks
 

Page 20 GAO-13-81 Defense Acquisitions

roadmaps, which can help guide and prioritize DOD’s investments.14

• U.S. Army Unmanned Aircraft Systems Roadmap 2010-2035—which 

is to inform warfighting functional concepts, contribute to capabilitiesbased assessments, and assist in the development of resourceinformed decisions on new technologies—mentions the concept of 

LTA vehicles, but does not specify the potential contributions of 

specific aerostats or airships.

For 

example:

• DOD’s Unmanned Systems Integrated Roadmap FY2011-2036—

which is to address the recent surge in the use of unmanned systems 

and describe a common vision for the continued integration of 

unmanned systems into the DOD joint force structure—includes a 

description of several aerostat and airship efforts underway, but it 

does not specifically cover how or whether aerostats and airships 

could contribute to DOD’s force structure.

Strategic frameworks and planning efforts can be essential to the 

effective oversight of portfolios, especially when they consist of multiple 

types of acquisitions in various stages of development, production, 

fielding, and sustainment. Such planning can help ensure DOD has the 

proper mix of platforms and a balanced investment portfolio among 

technology development, acquisitions, production, and sustainment 

activities, and thereby avoid unnecessary overlap in and duplication of 

effort. Adding aerostats and airships to the mix of other investments 

would add to the complexity of planning and oversight of relevant 

portfolios, but doing so could help to make (1) determinations of how 

aerostats and airships compare to other efforts and (2) effective trade-off 

decisions based on their capabilities and costs.

 

14Because of classification issues, we are not reporting on the extent to which DOD’s most 

recent ISR Integration Roadmap includes LTA platforms. However, we reported in 

GAO-11-465 that this roadmap does not represent an integrated investment strategy of 

ISR efforts across the department. Consequently, DOD was not able to readily identify all 

of its urgent needs efforts—that include aerostats or airships—or associated costs, 

including spending on ISR, because it had limited visibility into the entirety of the urgent 

needs submitted by warfighters.
 

Page 21 GAO-13-81 Defense Acquisitions

Since 2007, DOD significantly increased its investment in airship and 

aerostat efforts, in large part to respond to the urgent warfighter ISR 

needs in Iraq and Afghanistan, but also to demonstrate LTA technologies 

and deliver new capabilities. As a result, numerous organizations 

throughout DOD have pursued aerostat and airship development and 

acquisition efforts. For example, the Army oversees and manages the 

GARP testbed, JLENS, LEMV, and some high altitude airship efforts; the 

Air Force manages TARS; DARPA and the Air Force are responsible for 

ISIS; the Navy undertook Star Light and is currently responsible for PGSS 

and AAFL; and the Office of the Assistant Secretary of Defense for 

Research and Engineering is responsible for Project Pelican. Given the 

wide variety of efforts, DOD has taken some positive steps to coordinate 

the various aerostat and airship development and acquisition efforts it has 

underway. However, these efforts have mostly occurred at technical 

levels where working groups, consisting of technologists from industry 

and government, collaboratively address technical issues, as opposed to 

having a higher level authority to ensure coordination is effective. DOD 

officials identified various examples of these coordination efforts that have 

taken place among the military services and departments:

• The Army formed a working group in which the U.S. Navy Naval Air 

Systems Command (which manages the PGSS program) participated 

to develop plans to merge the PGSS and PTDS aerostat rapid fielding 

initiatives into a Persistence Surveillance Systems-Tethered program 

of record. This program of record transition is expected to occur in 

2014 and should help to ensure effective coordination between the 

efforts. 

• The National Aeronautics and Space Administration (NASA) Ames 

Research Center signed an interagency agreement in July 2011 with 

the DOD Office of the Director of Defense Research and 

Engineering’s Rapid Reaction Technology Office to develop a 

prototype airship referred to as Project Pelican. Project Pelican is the 

U.S. government’s only airship effort to demonstrate ballast-free 

variable-buoyancy control technology through which the vehicle can 

control its buoyancy (and therefore go up and down) without the use 

of ballast and/or ground personnel and ropes. Both agencies agreed 

to mitigate long-term technical risk by demonstrating this technology. 

NASA is providing acquisition support services to DOD by overseeing 

the contractor’s technical efforts and DOD is funding the effort.

• The Air Force and DARPA are currently collaborating on the ISIS 

project. A February 2009 memorandum of agreement between the Air 

Coordination Efforts 

Limited Mainly to 

Technical Collaboration
 

Page 22 GAO-13-81 Defense Acquisitions

Force and DARPA outlines their respective roles, responsibilities, and 

development objectives. The project involves developing a large radar 

aperture that is integrated into the structure of a station-keeping 

stratospheric airship supporting wide-area persistent surveillance, 

tracking, and engagement of ground, maritime, air, and space targets. 

DARPA is providing program management, technical direction, 

security management, and contracting support. The Air Force is 

providing resources for program management, demonstration efforts, 

equipment, and base operations and support. Additionally, the project 

has used lessons learned from the Army’s HALE-D project, as they 

are both designed to operate at a high altitude. However, ISIS is 

unique in that the radar system is integrated into the airship’s 

platform—the radar is part of the airship structure.

• LEMV coordination is occurring among various Army organizations 

and military services and agencies. For example, the Army obtained 

lessons learned and best practices for its development of LEMV by 

leveraging the Navy’s AAFL program and the Army’s HALE-D effort, 

and the Navy developed flight-to-ground operational procedures for 

LEMV. Additionally, the Army has had informal coordination with the 

Blue Devil Block 2 effort in the past. For example, originally both 

airships had several diesel engine commonalities (they used the same 

type of engine), and program officials shared challenges and solutions 

they discovered as part of the process to modify the engines to meet 

their respective requirements.

• The Navy’s AAFL serves as a flying laboratory and risk reduction testbed for sensors and other components and has assisted the Air Force 

with its Blue Devil Block 2 airship development. In 2011, the Air Force 

provided funding to the Navy to provide training to airship pilots to 

qualify them to fly the Blue Devil Block 2 airship.

While these efforts indicate some military services and organizations are 

sharing lessons learned and technical solutions, DOD may be able to 

realize additional opportunities for coordination within the agency and 

throughout the government. For example, DOD officials told us that 

coordination between the LEMV and Blue Devil Block 2 projects and 

opportunities to share lessons learned had been limited because of their 

concurrent and accelerated development pace. Also, according to a U.S. 

Central Command official, information sharing between the PTDS and 
 

Page 23 GAO-13-81 Defense Acquisitions

PGSS efforts has been limited, because the efforts are managed by 

different services, in areas such as test reports and operational impacts 

resulting from adverse weather.15 According to this official, better sharing 

of information could help to inform solutions for making aerostats more 

survivable. PGSS and PTDS program officials stated that the respective 

programs have steadily increased information sharing (including daily 

system status reports, aerostat incident reports, contracting information, 

budgets, and training programs of instruction) and collaboration on 

common aerostat issues (such as in-theater force protection for system 

operators, helium supply priorities, aerostat safety and weather 

information, and staff and crew tactical training).

The shortcomings in planning, insight, and collaboration may have made 

some airship efforts susceptible to duplication. We identified two airship 

development efforts—LEMV and Blue Devil Block 2—that were potentially 

duplicative at the time of our review. However, the potential duplication 

ended when the Air Force terminated the Blue Devil Block 2 program in 

June 2012. Most of the desired capabilities for LEMV and Blue Devil 

Block 2 were similar, as shown in table 3. According to DOD officials, 

these two programs were expected to demonstrate ISR capabilities; 

however, they are two different types of vehicles with different design 

objectives. LEMV is a hybrid airship demonstration that is developing a 

new platform and the Blue Devil Block 2 was a conventional airship that 

was to place sensors on a mature commercial-based platform. However, 

both were expected to have the capability to conduct ISR missions at low 

altitude, and share other operational characteristics. For example, both 

airships were to operate at the same operational altitude of 20,000 feet, 

were expected to handle a payload weight capacity of 2,500 pounds, and 

shared some of the same types of sensors. The two airship efforts also 

were being developed concurrently and were expected to be deployed to 

Afghanistan for testing and operations around the same time.

 

15The U.S. Central Command has a specific area of responsibility that covers 20 countries 

in the central area of the globe, including Afghanistan, Bahrain, Iran, and Iraq. U.S. 

Central Command is currently assessing how these assets are used differently across the 

military bases. Aerostats are vulnerable to adverse weather conditions in Iraq and 

especially Afghanistan. From April 2010 to June 2012, there were 58 PGSS and PTDS 

weather related major incidents. 

Potential Duplication 

Ended with Termination of 

Airship Effort
 

Page 24 GAO-13-81 Defense Acquisitions

Table 2: Comparison of LEMV and Blue Devil Block 2 Capabilities as of June 2012a

Airships

Long Endurance 

Multi-Intelligence 

Vehicleb Blue Devil Block 2

Payload weight capacity (pounds) 2,500 2,500

Operational altitude (feet above mean sea 

level)

20,000c 20,000

Envelope volume (cubic feet) 1,342,000 1,400,000

Sensor type

Electro-optical/infrared full motion video 

cameras

x x 

Wide area surveillance sensor x 

Signals intelligence sensor x x 

Ground motion target indicator radar x 

Communications relay system x x 

Source: GAO analysis of DOD data.

a

The Air Force terminated Blue Devil Block 2 in June 2012. 

b

According to the LEMV program office, the payload is flexible, as LEMV sensors are interchangeable 

based upon mission need. 

c

According to the LEMV program office, the current operational altitude requirement is 16,000 feet 

above mean sea level. 

The National Defense Authorization Act for Fiscal Year 2012 directed the 

Secretary of Defense to designate a senior official with principal 

responsibility for DOD’s airship programs.16

 

16Pub. L. No. 112-81, § 903 (2011).

In June 2012, the Deputy 

Secretary of Defense designated the Assistant Secretary of Defense for 

Research and Engineering as the senior official who will be responsible 

for the oversight and coordination of various airship-related programs 

across DOD. The statutory direction and appointment of the senior official 

are positive steps, but it is too early to assess the effectiveness of this 

official’s authorities and responsibilities in integrating and overseeing 

these activities. As of August 2012, the Office of the Assistant Secretary 

of Defense for Research and Engineering was defining the details relating 

to the authority, scope, and responsibilities of this new position. The 

overarching direction by the Deputy Secretary of Defense, in accordance 

with the statutory mandate, provides the senior official with authority over 

DOD Is Bolstering Its 

Oversight and 

Coordination but Future 

Investments Are Not 

Known
 

Page 25 GAO-13-81 Defense Acquisitions

airship-related efforts. Because aerostat efforts respond to some of the 

same warfighter requirements as airships, such as for persistent ISR, and 

share some of the same technologies used in airship development efforts, 

such as materials, design, and fabrication, common oversight of both 

airships and aerostats could enable DOD to have better visibility over all 

of its aerostat and airship efforts and help to ensure these efforts are 

effectively overseen, planned, and coordinated.

While DOD’s overall investment in this area has totaled nearly $7 billion in 

the past 6 years, near term funding estimates sharply decline beyond 

fiscal year 2012 and the level of future investment beyond fiscal year 

2016 is not known. Until DOD makes the decisions regarding its 

investments in this area, the proper role of the senior oversight official will 

not be known. If DOD decides to make significant future investments in 

aerostat and airship capabilities, the senior official could play a key role in 

shaping those investments. If no future investments are anticipated, the 

role of the senior official may necessarily be focused more narrowly on 

the systems that are fielded or already in development.

Aerostat and airship platforms are not a new concept, but they have 

recently been embraced in DOD because of their potential to provide 

continuous coverage capabilities quickly, especially in current military 

operations. Consequently, numerous organizations throughout DOD have 

pursued aerostat and airship development and acquisition efforts. DOD 

quickly initiated some of the larger programs with an eye toward 

leveraging commercial technologies and delivering capabilities to 

warfighters quickly to support current operations. But this rush came with 

high acquisition risk—particularly since there was a lack of knowledge 

about the amount of modifications and technology development that was 

required. Moreover, DOD’s limited oversight to ensure coordination of all 

of these efforts has resulted in ineffective integration of capabilities into 

broader strategic frameworks and limited investment knowledge and 

collaboration, making them susceptible to duplication. The appointment of

the Assistant Secretary of Defense for Research and Engineering as the 

senior official responsible for the oversight and coordination of various 

airship-related programs is a positive step, but the role of the position 

remains to be clearly defined. Yet, the future is uncertain; at this point, no 

substantive investment is planned for aerostat and airship capabilities. If 

significant future investment is planned, the senior official could play a 

valuable role in shaping investments, ensuring they maximize return by 

integrating them into broader plans so that their capabilities can be 

leveraged and not unnecessarily duplicative.

Conclusions
 

Page 26 GAO-13-81 Defense Acquisitions

To address shortcomings in oversight to improve coordination, we 

recommend that the Secretary of Defense take the following three actions 

based on the extent of the department’s future investments in aerostats 

and airships.

• If DOD decides to curtail future investment, focus on ensuring that it 

has an inventory and knowledge of all current and planned efforts in 

the short term.

• If DOD decides to significantly increase future investment, include 

aerostat and airship capabilities in strategic frameworks to ensure 

visibility into and coordination with relevant efforts, guide innovation, 

and prioritize investments.

• Ensure the roles and responsibilities of the Assistant Secretary of 

Defense for Research and Engineering, as the senior official 

responsible for the oversight and coordination of various airshiprelated programs, are defined and commensurate with the level of 

future investment.

We provided a draft copy of this report to DOD, DHS, and NASA for 

comment. In written comments on a draft of this report, DOD concurred 

with all three of our recommendations to address shortcomings in 

oversight to improve coordination of aerostat and airship development 

and acquisition efforts. DHS and NASA did not have formal comments on 

the draft report. Additionally, DOD, DHS, and NASA provided technical 

comments which were incorporated as appropriate.

DOD’s written comments are reprinted in appendix V. 

Recommendations for 

Executive Action

Agency Comments 

and Our Evaluation
 

Page 27 GAO-13-81 Defense Acquisitions 

We are sending copies of this report to appropriate congressional 

committees, the Secretaries of Defense and Homeland Security, and the 

Administrator of the National Aeronautics and Space Administration. In 

addition, the report will be available at no charge on GAO’s website at 

http://www.gao.gov. 

If you have any questions about this report, please contact me at 

(202) 512-4841 or chaplainc@gao.gov. Contact points for our Offices of 

Congressional Relations and Public Affairs may be found on the last page 

of this report. Key contributors to this report are provided in appendix VI. 

Cristina T. Chaplain 

Director 

Acquisition and Sourcing Management 
Appendix I: Scope and Methodology

Page 28 GAO-13-81 Defense Acquisitions

To determine what key aerostat and airship systems across the federal 

government are being developed and acquired, including funding, 

purpose, and status of these systems, we reviewed documentation and 

interviewed officials on the status and progress of aerostat and airship 

development efforts in areas such as requirements, funding, costs, 

budgets, schedule, contracting, technology maturation, and actual or 

planned operational characteristics. In doing so, we developed an 

inventory of key airship and aerostat development and acquisition efforts 

which enabled a comparison of platform types, performance attributes, 

and costs. As part of identifying the universe of aerostat and airship 

efforts in the federal government, we interviewed agency officials and 

asked them about any knowledge they have regarding other systems that 

may currently exist. We also conducted Federal Procurement Data 

System—Next Generation (FPDS-NG) database and internet searches to 

inform ourselves about existing efforts; the internet searches included 

unclassified searches and background research. We corroborated and 

confirmed the accuracy of the FPDS-NG and internet search information 

with applicable agencies. Based on a review of funding data collected 

from agencies that we contacted as well as from presidential budget 

estimates and Selected Acquisition Reports as available, we determined 

that our definition of “key aerostat and airship systems being planned, 

developed, and acquired” includes two key criteria (1) total funding of $1 

million or more from fiscal years 2007 to 2012, and (2) efforts to plan, 

develop or acquire systems that include both a platform and payload 

(such as sensors or cargo) capability. We analyzed documentation and 

interviewed officials from various offices of the Secretary of Defense; 

various offices within the Army, Navy, and Air Force; U.S. Central 

Command; Defense Advanced Research Projects Agency; Defense 

Logistics Agency; and offices of the Joint Chiefs of Staff. We also 

analyzed documentation and interviewed officials from civil agencies, 

including the Department of Homeland Security, Department of Energy, 

Environmental Protection Agency, National Oceanic and Atmospheric 

Administration, National Aeronautics and Space Administration, and 

Office of the Director of National Intelligence. We did not examine the 

development and utilization of lighter-than-air (LTA) technologies outside 

of the federal government.

To identify any technical challenges these key aerostat and airship efforts 

may be facing, we analyzed documentation and interviewed officials from 

the organizations mentioned above. We used the collected information to 

assess any identified technical problems impacting the funding, cost, 

schedule, and performance of airships and aerostats.

Appendix I: Scope and Methodology
Appendix I: Scope and Methodology

Page 29 GAO-13-81 Defense Acquisitions

To determine how effectively the various key aerostat and airship efforts 

are being overseen to ensure coordination, and identify any potential for 

duplication, we assessed aerostat and airship investments, acquisitions, 

capabilities, and operations by analyzing documents and interviewing 

officials from the organizations listed above, analyzing the inventory of 

key efforts developed under our first objective, and reviewing prior GAO 

work for relevant criteria. Specifically, we assessed oversight at the 

programmatic and enterprise levels by reviewing organizational roles, 

responsibilities, and authorities as they relate to aerostat and airship 

development, acquisition, and operations efforts. We also determined the 

extent to which plans and planning activities integrated aerostat and 

airship development and acquisition efforts and capabilities within the 

Department of Defense (DOD). Reviewed plans and planning activities 

included architectures, roadmaps, investment plans, and requirements 

development. We also used the information relating to various aspects of 

the development and acquisition efforts, such as requirements, and actual 

or planned performance attributes, to assess whether any of the efforts 

are potentially duplicative.

We conducted this performance audit from June 2011 to October 2012 in 

accordance with generally accepted government auditing standards. 

Those standards require that we plan and perform the audit to obtain 

sufficient, appropriate evidence to provide reasonable basis for findings 

and conclusions based on our audit objectives. We believe that the 

evidence obtained provides a reasonable basis for our findings and 

conclusions based on our audit objectives.
Appendix II: Examples of Civil Government 

Use of Aerostats 

Page 30 GAO-13-81 Defense Acquisitions

Table 3: Civil Government Agencies’ Aerostat Usage

Essentials Purpose and status

Lead agency: Department of Commerce 

(DOC), National Oceanic and Atmospheric 

Administration (NOAA)

Number of units: 2

Total costs: $35,475

The purpose of DOC’s NOAA aerostats is to collect wind data up to approximately 1,641 

feet above the ground. NOAA procured the aerostats, ground station, and supporting 

equipment in September 2011.

Lead agency: Department of Energy (DOE), 

Office of Science

Number of units: 1

Fiscal year (FY) 10 to FY12 operations and 

maintenance costs: $275,529

Over the past 20 years, DOE’s Office of Science has supported a national scientific user 

facility called the Atmospheric Radiation Measurement Climate Research Facility, which 

is a unique system for continuous observations, capturing fundamental data on 

atmospheric radiation, cloud and aerosol properties. Since fiscal year 2010, DOE’s 

Office of Science has funded the use of a contracted aerostat to support research 

carried out through the Atmospheric Radiation Measurement Climate Research Facility.

Lead agency: Environmental Protection 

Agency (EPA)

Number of units: 5

FY09 to FY11 aerostats and equipment 

purchase costs: $35,135

In 2009 EPA developed a tethered, aerostat-lofted sampling package for the purpose of 

sampling air emissions from open sources. Multiple aerostats have been purchased to 

support increasing payloads. EPA’s program has been largely funded through a project 

with DOD’s Strategic Environmental Research and Development Program to 

characterize emissions from open burning and open detonation of military ordnance. 

EPA will continue its emissions monitoring program using aerostats only if it can secure 

additional funding. Otherwise, the program will cease to exist. 

Lead agency: National Aeronautics and 

Space Administration (NASA)

Number of units: For the most part, NASA 

does not own aerostats, but funds research 

using them

Costs: NASA reported funding a total of 

$150,000 for research using aerostats and 

approximately $35,000 for aerostats at the 

Wallops Flight Facility

According to NASA, they occasionally fund research that deploys tethered balloons for 

atmospheric and weather observations. Also, NASA’s Jet Propulsion Laboratory 

continues to use tethered balloons for climate research. NASA plans to continue funding 

atmospheric and weather research using tethered balloons. For example, in fiscal year 

2013, NASA plans to fund atmospheric and weather research that will use two tethered 

balloons in Yen Bai, Vietnam. Furthermore, NASA Goddard Space Flight Center’s 

Wallops Flight Facility owns and operates small commercially produced tethered blimps 

(advertising type) within the restricted airspace over Wallops Island. These aerostat 

systems are used for visibility markers during range operations and for lifting miniature 

experimental instrument packages.

Source: GAO analysis of U.S. government data.

Appendix II: Examples of Civil Government 

Use of Aerostats
Appendix III: DOD Aerostat and Airship 

Development, Acquisition, and Operations 

Efforts

Page 31 GAO-13-81 Defense Acquisitions

Table 4: Aerostat and Airships Essentials, Purpose, and Status

Essentialsa Purpose and status

Aerostats

Name: Geospatial Airship Research Platform 

(GARP) 

Lead service/agency: Army

Prime contractor: Aerostar and Lindstrand 

Technologies

Total number of operational contractor personnel: 

8; 4 each for launch operation

Number of units: 2

Operational altitude

(feet above mean sea level): Up to 3,000 above 

ground level

Sensor type: various, including electro-optical, 

infrared, and spectral cameras; radars; and 

communication relay payloads

Fiscal Year (FY) 08-FY10 costs: $9.4 million

According to an official from the Army’s U.S. Army Space and Missile Defense 

Command Battle Laboratory, the facility uses GARP as a testing platform for 

intelligence, surveillance, and reconnaissance (ISR) and communications 

payloads.

Name: Joint Land Attack Cruise Missile Defense 

Elevated Netted Sensor (JLENS)

Lead service/agency: Army

Prime contractor: Raytheon

Total number of operational contractor personnel: 

not applicable, because system is not yet fielded

Number of units: 2

Operational altitude

(feet above mean sea level): 10,000

Sensor type: radars

FY07-FY16 costs:

$2,555.6 million

The Army’s JLENS major defense acquisition program, established in 1996 as 

the Joint Aerostat Project, will provide over-the-horizon detection and tracking 

of land-attack cruise missiles and other targets. The Army is developing 

JLENS in two spirals. Spiral 1 is complete and served as a test bed to 

demonstrate the concept. Spiral 2 will utilize two aerostats with advanced 

sensors for surveillance and tracking, as well as mobile mooring stations, 

communications payloads, and processing stations. JLENS will provide 

surveillance and engagement support to other systems.

JLENS entered the system development phase in August 2005. As we 

previously reported, the program has experienced design issues associated 

with the mobile mooring transport vehicle, as well as schedule delays caused 

by synchronization of JLENS with the Army’s Integrated Air and Missile 

Defense program. According to program acquisition documentation, JLENS 

was originally scheduled to enter production in September 2010. However, 

that same month, an aerostat accident resulted in the loss of one of the 

JLENS platforms. The accident, as well as recent system integration 

challenges, caused delays to the program’s production decision. Moreover, 

according to program acquisition documentation, the JLENS program incurred 

a critical Nunn-McCurdy breach for program acquisition unit cost with the 

submission of the fiscal year 2013 President’s Budget due to a 100 percent 

reduction in planned procurement quantities. The total program quantity was 

reduced from 16 to 2 aerostats. In May 2012, the Under Secretary of Defense 

for Acquisition, Technology and Logistics directed the Secretary of the Army to 

restructure the JLENS program to consist of two aerostats. The Secretary of 

the Army was also directed to provide a status of the program, based on 

development test and evaluation results, during an interim program review 

scheduled for the third quarter of fiscal year 2013.

Appendix III: DOD Aerostat and Airship 

Development, Acquisition, and Operations 

Efforts 
Appendix III: DOD Aerostat and Airship 

Development, Acquisition, and Operations 

Efforts

Page 32 GAO-13-81 Defense Acquisitions

Essentialsa Purpose and status

Name: Persistent Ground Surveillance System 

(PGSS) 

Lead service/agency: Navy

Prime contractor: Aerostar and TCOM

Total number of operational contractor personnel: 

400; 7 to 8 contractors needed per site

Number of units: 59

Operational altitude

(feet above mean sea level): 6,000 to 9,000

Sensor type: electro-optical/ infrared sensors; 

unattended transient acoustic measurement and 

signatures intelligence sensor, wide-area sensor 

system, and communications relay system

FY09-FY13 costs: $2,108.4 million

The Office of the Secretary of Defense for Acquisition, Technology and 

Logistics initiated PGSS in fiscal year 2010 as a joint capability technology 

demonstration in response to a series of commanders’ urgent requests for 

additional ISR support in Afghanistan. PGSS is intended to provide a family of 

affordable and small footprint aerostat surveillance systems.

A total of 59 PGSS aerostats have been purchased by the Navy for 

deployment to forward operating bases in Afghanistan: 31 were built in fiscal 

year 2010, and 28 in fiscal year 2011. Although the Navy acquires and 

operates PGSS aerostats, the Army funds the program and has proposed its 

inclusion in a new program of record—named Persistent Surveillance SystemTethered (PSST). A capability development document for PSST should be 

finalized by the end of the summer. According to DOD, PGSS aerostats 

deployed in the U.S. Central Command area of responsibility have been 

effective ISR assets.

Name: Persistent Threat Detection System (PTDS)

Lead service/agency: Army 

Prime contractor: Lockheed Martin

Total number of operational contractor personnel: 

About 650; 8 to 10 contractors needed per site

Number of units: 66

Operational altitude

(feet above mean sea level): 8,000

Sensor type: electro-optical/ infrared cameras, 

unattended transient acoustic measurement and 

signatures intelligence sensor, ground moving 

target indicator/dismount moving target indicator 

radar, and a wide-area sensor system

FY07-FY16 costs: $3,170.5 million

Like the PGSS aerostats, PTDS aerostats were deployed (to Iraq in 2004 and 

Afghanistan in 2007) in response to a series of commanders’ urgent requests 

for additional ISR support. However, PTDS is a bigger system than PGSS that 

is practically immobile. The Army plans to have a total of 66 PTDS aerostats; 

34 have been deployed to Afghanistan, one is used for testing in the United 

States, and the remainder are in production or in transit for use in Afghanistan. 

According to DOD, PTDS aerostats deployed in the U.S. Central Command

area of responsibility have been effective ISR assets. Like PGSS, the Army 

also proposed PTDS for inclusion in the PSST program of record. However, 

the Army is expected to keep the PGSS aerostats and phase out PTDS. Upon 

completion of operations in Afghanistan, the Army is considering deploying a 

few PTDS for training and for use by the Department of Homeland Security 

(DHS). 

Name: Rapid Aerostat Initial Development (RAID)

Lead service/agency: Army

Prime contractor: Raytheon

Total number of operational contractor personnel: 

252

Number of units: 21

Operational altitude

(feet above mean sea level): 1,000 above ground 

level

Sensor type: thermal imaging sensors

FY07-FY16 costs: $225.0 million

The RAID aerostats were first deployed to Afghanistan in 2001 to provide 

force protection in response to an urgent need request. However, due its small 

size, it was never ideal for use in inclement weather. As a result, the Army 

acquired a larger aerostat—PTDS. The Army procured a total of 21 RAID 

aerostats—19 were deployed to Iraq and 2 were used as training assets in the 

United States. The 19 RAID aerostats deployed to Iraq were moved to Kuwait 

and are no longer in use.
Appendix III: DOD Aerostat and Airship 

Development, Acquisition, and Operations 

Efforts

Page 33 GAO-13-81 Defense Acquisitions

Essentialsa Purpose and status

Name: Rapidly Elevated Aerostat Platform (REAP)-

XL B

Lead service/agency: Army and Navy

Prime contractor: Information Systems Laboratories

Total number of operational contractor personnel: 

Army: 4, 2 per unit; Navy: unknown

Number of units: 3

Operational altitude

(feet above mean sea level): Army: 1,000 above 

ground level; Navy: Up to 1,000

Sensor type: Army: electro-optical/infrared/short 

wave infrared cameras; Navy: communication 

equipment

Navy Working Capital Fund Capital Investment 

Program FY 10 costs: $668,000

Army: FY 11 costs: $4.7 million

The Army needed a smaller aerostat for persistent surveillance during short 

duration missions, for example, to rebuild a bridge, or at a polling location 

during elections, in response to an urgent need request. REAP-XL B can be 

launched from the back of a High Mobility Multipurpose Wheeled Vehicle 

(Humvee) by two people in 10 minutes. The Navy tested a REAP-XL B 

platform as an extended communications relay system that can be operated 

from shore to reduce testing and integration costs.

Two REAP-XL B prototype aerostats were deployed to Afghanistan. According 

to an Army official, officials from U.S. Central Command and the Army are 

conducting a 90-day assessment of REAP-XL’s operational performance. 

Although it is too early to determine if REAP-XL will be part of a program of 

record, as many as 35 more could be acquired if it is determined that they can 

operate in Afghanistan’s high altitude, according to an Army Intelligence 

Futures Directorate official. The Navy’s REAP-XL B aerostat is currently in 

storage, according to the Navy. 

Name: Tethered Aerostat Radar System (TARS) 

Lead service/agency: Air Force

Current sustainment service contractor: ITT 

Systems 

Total number of operational contractor personnel: 

approximately 249 at 8 operational sites, logistics 

center, and program management office

Number of units: 8

Operational altitude

(feet above mean sea level): 14,000 to 15,000 

depending on model type

Sensor type: radars and communication systems

FY07-FY16 costs: $350.0 million

The TARS aerostat radar network began operations identifying low-flying, 

small aircraft involved in drug trafficking along the southern U.S. border in 

1978. Currently, there are eight operational TARS sites supporting DOD’s 

counterdrug detection and monitoring mission, as well as North American 

Aerospace Defense Command’s air sovereignty mission. TARS sites are 

treated as remote surveillance sensor sources. Surveillance data from each 

radar is transmitted to DOD and DHS operations centers.

TARS is in the operational sustainment phase of the acquisition life-cycle and 

there are currently no plans to replace, augment, or complement its baseline 

capabilities. DHS is funding science and technology research that could 

enhance future TARS sensor imaging capabilities.

Airships

Name: Advanced Airship Flying Laboratory (AAFL)

Lead service/agency: Navy

Prime contractor: Integrated Systems Solutions, 

Inc.

Total number of operational contractor personnel: 

20

Number of units: 1

Operational altitude (feet above mean sea level): 

1,000 to 7,500

Sensor type: AAFL operates as a surrogate testbed for various communications and sensor 

systems 

FY07-FY12 costs: $14.1 million

Since 2007, the surrogate test-bed airship has been used across the country 

to evaluate a variety of DOD and other U.S. government sensor and 

communication systems (including intelligence, surveillance, and 

reconnaissance (ISR) assets) in an airborne environment. The airship also 

assisted in the search for oil and distressed wildlife during the 2010 

Deepwater Horizon disaster.

The Navy is conducting pilot training in the United States in support of Army 

programs. The Army has provided sufficient funding for continued operations 

through March 2013. 
Appendix III: DOD Aerostat and Airship 

Development, Acquisition, and Operations 

Efforts

Page 34 GAO-13-81 Defense Acquisitions

Essentialsa Purpose and status

Name: Blue Devil Block 2

Lead service/agency: Air Force

Prime contractor: MAV6

Total number of operational contractor personnel: 

to be determined

Number of units: 1

Operational altitude (feet above mean sea level): 

20,000

Sensor type: Wide area field of view electro-optical 

and infrared cameras; narrow field of view electrooptical and infrared full motion video cameras; and 

signals intelligence sensor

FY10-FY12 costs: $243.6 million

A contract was awarded in October 2010 to begin the Blue Devil Block 2 

airship development initiative in response to U.S. Central Command urgent 

requirements for ISR capabilities to address the growing need for persistent 

improvised explosive device surveillance and detection in Afghanistan. The 

Blue Devil Block 2 airship is intended to demonstrate persistent multiintelligence ISR capabilities for 3 to 7 days, at an altitude of 20,000 feet.

The program was terminated effective June 2012. It had been scheduled to 

deploy “beyond September 2012,” at least one year later than originally 

scheduled. However, the contractor has been directed to pack and crate the 

airframe and transport it to an Air Force storage facility at the end of the 

contract period. As a result, the Air Force will not deploy the Blue Devil Block 

2 airship to Afghanistan as planned. 

Name: High Altitude Endurance-Demonstrator 

(HALE-D)

Lead service/agency: Army

Prime contractor: Lockheed Martin

Total number of operational contractor personnel: 

not applicable, HALE-D is a science and technology 

effort

Number of units: 1

Operational altitude (feet above mean sea level): 

60,000

Sensor type: high resolution electro-optical camera

FY08-FY11 costs: $36.3 million

HALE-D is a science and technology effort that is part of the Army’s High 

Altitude Airship program, intended to demonstrate persistent on-station ISR 

capabilities at high altitudes. A solar powered airship, HALE-D is supposed to 

fly at an altitude of 60,000 feet for more than 14 days.

In July 2011, on its first flight, HALE-D experienced a technical failure 3 hours 

into a planned 14-day mission. Its envelope and solar cells were destroyed, 

and its payload was damaged by a fire during recovery operations. According 

to the program office, the project does not currently have funding for continued 

demonstration efforts.

Name: HiSentinel

Lead service/agency: Army

Prime contractor: Southwest Research Institute

Total number of operational contractor personnel: 

not applicable, HiSentinel is a science and 

technology effort

Number of units: 2; HiSentinel50 and HiSentinel80

Operational altitude (feet above mean sea level): 

HiSentinel50: 66,300; HiSentinel80: 66,000

Sensor type: HiSentinel50: High resolution camera 

and communication system; HiSentinel80: Hiresolution electro-optical camera and 

communications system

FY07-FY11 costs: $11.2 million

Like HALE-D, HiSentinel is a science and technology effort that is part of the 

Army’s High Altitude Airship program, intended to demonstrate persistent onstation ISR capabilities at high altitudes. Specifically, both HiSentinel 50 and 

80 are solar-powered airships intended to fly at altitudes of approximately 

66,000 feet for greater than one day. They are both in a flaccid state on the 

ground prior to launch and the envelopes achieve their final shape as the 

helium gas within expands with increasing altitudes.

In June 2008, HiSentinel50 flew up to an altitude of 66,400 feet, and 

maintained that altitude for a total of 3 minutes. In November 2010, the followon demonstrator, HiSentinel80, experienced a propulsion system failure and 

landed 8 hours into a planned 24-hour mission. Like Hale-D, the program 

office stated that the project does not currently have funding for continued 

demonstration efforts.
Appendix III: DOD Aerostat and Airship 

Development, Acquisition, and Operations 

Efforts

Page 35 GAO-13-81 Defense Acquisitions

Essentialsa Purpose and status

Name: Integrated Sensor is Structure (ISIS)

Lead service/agency: Defense Advanced Research 

Projects Agency (DARPA) and Air Force

Prime contractor: Lockheed Martin

Total number of operational contractor personnel: 

not applicable, ISIS is a demonstration prototype

Number of units: 1

Operational altitude (feet above mean sea level): 

65,000

Sensor type: air, ground, and surface moving target 

indicator radar system

FY07-FY14 costs: $506.1 million

The joint DARPA and Air Force ISIS project, initiated in 2004 as a science and 

technology effort, is intended to develop and demonstrate a radar sensor of 

unprecedented proportions that is fully integrated into a stratospheric airship 

to support the need for persistent wide-area surveillance, tracking, and 

engagement of time-critical air and ground targets in urban and rural 

environments. The demonstrator airship is expected to fly for 365 days at an 

altitude of 65,000 feet. ISIS has experienced technical challenges stemming 

from subsystem development and radar antennae panel manufacturing. 

Consequently, earlier this year DARPA temporarily delayed airframe 

development activities, and instead will mainly focus on radar risk reduction 

activities. During this time period, the ISIS team will develop an airship risk 

reduction plan and conduct limited airship activities. Based on the radar and 

airship risk reduction studies, DARPA will reassess the future plan for ISIS 

with the Air Force.

Name: Long Endurance Multi-Intelligence Vehicle 

(LEMV) 

Lead service/agency: Army

Prime contractor: Northrop Grumman

Total number of operational contractor personnel: 

35

Number of units: 1

Operational altitude (feet above mean sea level): 

20,000

Sensor type: Electro-optical/infrared full motion 

video cameras; ground motion target indicator 

radar; communication relay package; and signal 

intelligence system. According to the LEMV 

program office, the payload is flexible based upon 

mission need as LEMV sensors are 

interchangeable, based upon mission need.

FY07-FY15 costs: $356.2 million

LEMV is a technology demonstration project, expected to develop a hybrid 

prototype airship for ISR purposes in a forward combat environment. The 

project was initiated in response to an urgent need request. The Army is 

supposed to complete system level development and testing within the United 

States within 18 months after contract award (June 2010) and be ready for 

transport to Afghanistan for a joint military utility assessment and follow-on 

demonstration. The required on-station duration time is 21 days at an altitude 

of 20,000 feet. Pending the results of the joint military utility assessment and 

other reviews and evaluations, the Army will determine whether or not to 

pursue a program of record.

According to the program office, the LEMV hybrid airship is scheduled to 

undergo 33 manned flights totaling approximately 500 hours. The Army 

successfully launched and recovered LEMV during its first flight in August 

2012. The initial date for deployment was January 2012; currently, the 

deployment date is indefinite. LEMV development is behind schedule 10 

months (representing about a 56 percent schedule increase) due to issues 

with fabric production, getting foreign parts through customs, adverse weather 

conditions causing the evacuation of work crews, and first time integration and 

testing issues. Also, LEMV is 12,000 pounds overweight because it has 

weight issues with sub-systems, such as tailfins, exceeding weight thresholds. 

According to the program, the increased weight reduces the airship’s 

estimated on-station endurance at an altitude of 20,000 feet from the required 

21 days to 4 to 5 days, representing at least a 76 percent reduction However, 

current plans, according to program officials, call for operating the airship at 

16,000, feet which should enable on-station duration time to be 16 days with 

minimal impacts to operational effectiveness (other than about a 24 percent 

reduction to on-station endurance). The biggest risk to program development 

is the ambitious schedule of 18 months. The Army identified a fiscal year 2012 

funding shortfall of $21.3 million resulting from the need for additional 

engineering and production support to mitigate and resolve technical issues at 

the LEMV assembly facility.
Appendix III: DOD Aerostat and Airship 

Development, Acquisition, and Operations 

Efforts

Page 36 GAO-13-81 Defense Acquisitions

Essentialsa Purpose and status

Name: Project Pelican

Lead service/agency: Office of the Assistant 

Secretary of Defense for Research and Engineering 

(OASDR&E), National Aeronautics and Space 

Administration (NASA), and the Air Force Research 

Laboratory

Prime contractor: Aeros Aeronautical Systems 

Corporation

Total number of operational contractor personnel: 

not applicable, the airship is a technology 

demonstrator and is not intended for operational 

performance beyond the requirements of the 

demonstration activities

Number of units: 1

Operational altitude (feet above mean sea level): 

not applicable, the airship is a technology 

demonstrator and is not intended for operational 

performance beyond the requirements of the 

demonstration activities

Sensor type: not applicable, the airship is a 

technology demonstrator and is not intended for 

operational performance beyond the requirements 

of the demonstration activities

FY08-FY11 costs: $42.4 million

According to OASDR&E program officials, Project Pelican was initiated in 

2008 as a science and technology demonstration effort intended to develop a 

hybrid airship with a rigid internal structure and test airship buoyancy control 

technologies. NASA’s Ames Research Center, the contract servicing agent for 

OASDR&E, and the Air Force Research Laboratory are also involved in the 

management and oversight of this project that, according to the NASA Ames 

Research Center program office, “is considered a game changer in the airship 

world” because the key effort is to control buoyancy without using external 

ballast. The airship built under Project Pelican is not intended for operational 

performance beyond the requirements of the demonstration activities. But, 

according to OASDR&E program officials, once all the necessary technologies 

have been proven to work together, the effort will be scaled to provide ISR or 

heavy lift capabilities in the long-term. According to the NASA Ames Research 

Center program office, the Project Pelican demonstrator airship is expected to 

be tested at the end of fiscal year 2012.

Name: Star Light

Lead service/agency: Navy

Prime contractor: Global Near Space Services

Total number of operational contractor personnel: 8

Number of units: 1

Operational altitude (feet above mean sea level): 

65,000 to 85,000

Sensor type: no specific sensor was identified 

under the demonstration effort

FY10 costs: $2.1 million

The Star Light airship, initiated as a science and technology effort, was 

expected to operate at between 65,000 to 85,000 feet, with an on station 

duration of between 30 to 120 days, depending on the time of year and the 

wind speed. A specific sensor was never identified. The program began and 

was terminated in 2010 due to insufficient funding.

Source: GAO analysis of DOD data.

a

Funding data have been adjusted to fiscal year 2012 dollars. 
Appendix IV: Funding Calculations for 

Aerostats and Airships, Fiscal Years 2007 

through 2016

Page 37 GAO-13-81 Defense Acquisitions

Table 5: Total Aerostat Funding, Fiscal Years 2007 through 2016

(In millions of fiscal year 2012 dollars, rounded to nearest tenth)

Fiscal year

Effort 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 Total

Geospatial Airship 

Research Platform 

(GARP) 

$9.4

Research,

development, test, and 

evaluation (RDT&E)

$3.2 $2.9 $3.3

Joint Land Attack 

Cruise Missile 

Defense Elevated 

Netted Sensor 

(JLENS) 

$2,555.6

RDT&E $255.9 $488.6 $357.1 $325.7 $405.1 $327.3 $187.4 $92.4 $30.9 $22.6 $2,493.1

Military Construction $20.5 $42.0 $62.5

Persistent Ground 

Surveillance System 

(PGSS) 

$2,108.4

RDT&E $1.5 $1.5 $20.0 $23.1

Procurement $105.7 $454.6 $182.9 $191.0 $182.1 $1,116.4

Operations and

Maintenance (O&M) 

$7.8 $13.68 $163.3 $366.0 $418.3 $968.9

Persistent Threat 

Detection System 

(PTDS) 

$3,170.5

RDT&E $0.3 $0.4 $4. 6 $0.0 $0.1 $5.4

Procurement $26.3 $299.1 $776.1 $181.9 $28.0 $15.7 $15.5 $17.1 $16.8 $1,376.5

O&M $47.4 $60.9 $79.4 $104.7 $108.0 $339.6 $350.3 $349.3 $349.0 $1,788.6

Rapid Aerostat Initial 

Development (RAID)

$225.0

Procurement $7.4 $7.4

O&M $12.2 $20.0 $20.7 $21.6 $22.3 $23.0 $23.6 $24.2 $24.7 $25.3 $217.5

Rapidly Elevated 

Aerostat Platform 

(REAP)-XL B

$5.3

Navy Working Capital 

Fund Capital 

Investment Program

$0.7

RDT&E $4.7

Appendix IV: Funding Calculations for 

Aerostats and Airships, Fiscal Years 2007 

through 2016
Appendix IV: Funding Calculations for 

Aerostats and Airships, Fiscal Years 2007 

through 2016

Page 38 GAO-13-81 Defense Acquisitions

Fiscal year

Effort 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 Total

Tethered Aerostat 

Radar System 

(TARS) 

$350.0

RDT&E $2.0 $2.0

Procurement $5.4 $5.4 $7.2 $5.3 $5.4 $5.6 $5.8 $5.5 $2.8 $3.8 $52.3

O&M $31.3 $28.9 $28.1 $29.7 $29.5 $29.7 $29.6 $29.3 $29.7 $29.8 $295.7

Source: GAO analysis of DOD data.

Table 6: Total Airship Funding, Fiscal Years 2007 through 2016

(In millions of fiscal year 2012 dollars, rounded to nearest tenth)

Fiscal year

Effort 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 TOTAL

Advanced Airship 

Flying Laboratory 

(AAFL, also known 

as MZ-3A) 

$14.1

RDT&E $0.2 $0.6 $1.6 $2.4

O&M $6.2 $5.6 $11.7

Blue Devil Block 2 $243.6

RDT&E $54.4 $126.2 $63.0 $243.6 

High Altitude 

EnduranceDemonstrator 

(HALE-D)

$36.3

RDT&E $16.7 $11.5 $5.3 $2.8 $36.3

Hi-Sentinel $11.2

RDT&E $1.3 $4.1 $0.7 $2.2 $2.8 $11.2

Integrated Sensor is 

Structure (ISIS)

$506.1

RDT&E $25.1 $30.5 $81.2 $250.3 $24.1 $60.2 $34.7 $506.1

Long Endurance 

Multi-Intelligence 

Vehicle (LEMV)

$356.2

RDT&E $130.9 $101.4 $43.6 $25.8 $28.1 $26.5 $356.2

Project Pelican $42.4

RDT&E $6.3 $10.9 $14.4 $10.9 $42.4

Starlight $2.1

RDT&E $2.1 $2.1

Source: GAO analysis of DOD data.
Appendix V: Comments from the Department 

of Defense

Page 39 GAO-13-81 Defense Acquisitions

Appendix V: Comments from the Department 

of Defense

The report number 

changed from 

GAO-12-906 to 

GAO-13-81.
Appendix V: Comments from the Department 

of Defense

Page 40 GAO-13-81 Defense Acquisitions
Appendix V: Comments from the Department 

of Defense

Page 41 GAO-13-81 Defense Acquisitions
Appendix VI: GAO Contact and 

Staff Acknowledgments

Page 42 GAO-13-81 Defense Acquisitions

Cristina T. Chaplain, (202) 512-4841 or chaplainc@gao.gov. 

In addition to the contact named above, key contributors to this report 

were Art Gallegos, Assistant Director; Ami Ballenger; Jenny Chanley; 

Maria Durant; Arturo Holguín; Rich Horiuchi; Julia Kennon; Tim Persons; 

Sylvia Schatz; Roxanna Sun; and Bob Swierczek.

Appendix VI: GAO Contact and Staff 

Acknowledgments 

GAO Contact

Staff 

Acknowledgments

(121000)
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