AFS

- 15

- 093

- E Exemption No. 11320

UNITED STATES OF AMERICA

DEPARTMENT OF TRANSPORTATION

FEDERAL AVIATION ADMINISTRATION WASHINGTON, DC 20591

In the matter of the petition of

ZEE.AERO, INC Regulatory Docket No. FAA

- 2014

- 0882

for an exemption from § 91.151(a)(1) of Title 14, Code of Federal Regulations

DENIAL OF EXEMPTION

By letter dated October 20, 2014, Mr. Tom Gunnarson, Lead of Certification and Regulatory Affairs, Zee.Aero Inc. (Zee.Aero), 2700 Broderick Way, Mountain View, CA 94043 petitioned the Federal Aviation Administration (FAA) on behalf of Zee.Aero for an exemption from § 91.151(a)(1) of Title 14, Code of Federal Regulations (14 CFR). The proposed exemption, if granted, would allow its manned aircraft using electric propulsion to fly with a reduced “fuel” reserve during their FAA approved research and development (R&D) flight
test program.

The petitioner requires relief from the following regulation[s]:

Section 91.151 Fuel requirements for flight in VFR conditions prescribes, in pertinent part,

that

(a) No person may begin a flight in an airplane under VFR conditions unless (considering wind and forecast weather conditions) there is enough fuel to fly to

the firs t point of intended landing and , assuming normal cruising speed

-

(1) During the day, to fly after that for at l east 30 minutes.2

The petitioner supports its request with the following information:

The petitioner states t he aircraft under development incorporate s unique design and system features that provide an equivalent or higher level of safety compared to liqu id

- fueled spark ignition propulsion systems. The petitioner states that the aircraft will be flown under a tightly controlled set of conditions, and a test team will monitor airport traffic conditions, weather conditions and the health of aircraft systems during all test flights

. Additionally, Zee.Aero

states that t hese procedures will mitigate local air traffic conflicts and protect persons and
property on the ground. Relevant aircraft safety characteristics, operational controls

, and safety features liste d by Zee.Aero include:

Aircraft Safety Characteristics

• The Zee.Aero electric propulsion system (EPS) utilizes solid

- state electronics and redundancies with few moving parts. This is in contrast with a carburetor/fuel injector system, fuel lines and assoc iated metering systems with the inaccuracies inherent in a traditional liquid fueled propulsion system.

• A battery and energy flow management system prov ides precise real

- time state of energy remaining and time

- remaining warnings to the pilot.

• An independ ent health monitoring system and proprietary battery architecture assures a high level of protection from thermal runaway or other electrical system failure.

• A ballistic recovery parachute is available to recover pilot and vehicle in an emergency.

Operat ional Safety Plans

• Detailed failure scenario fight planning enable s the pilot and flight test team to ensure that the planned reserve is always available and that communication of planned landing will be accurate and complete. This type of planning inclu des, but is not limited to;

o A safe cone of operations established for each fl ight that enables an engine out glide to a runway for either an upwind or downwind landing.

o Ground station and cockpit monitoring to keep fl ight operations within the safe

cone o f operations at all times.

o Takeoff, departure, and landing profiles that prescribe landing options as a function of altitude and aircraft position.

• The EPS is continuously monitored both in the cockpit and via a ground test station. Hardware redundancy a nd operational restrictions have been establi shed to mitigate the

effects of EPS failures.3

• All test flights will be conducted in visual meteorological conditions under day visual flight rules, outside controlled air space, within sight of the base airport and only when

sustained winds are 10 knots or less.

• The aircraft will only be flown by highly qualified tes t pilots listed in the “ approved ” flight test program. Pilots will also receive mission simulation and flight training in a

Z

- P101 specific fixed base, immersive aircraft simulator with r ealistic flight instruments, control stick and throttle, and aerodynamic performance modeling

.

With these aircraft safety features and operational controls, Zee.Aero is confident that its airplane can be operated as safely as traditional gas

- powered airplanes operating under § 91.151.

The petitioner states that the request for a lower fuel reserve is also based on endurance restrictions due to the significant weight penalty of currently available battery systems. Further, Zee.Aero has determined that the s tate of the art batteries for this type of application have, at best, nine times less energy density by weight than aviation gasoline. Therefore, to stay within safe design limits, the energy storage system in th e initial Zee.Aero test airplanes will only allow a maximum 25

- minute flight at cruise power with a 5

- minute reserve. Adding more batteries to extend flight time will not be feasible during the test phase.

Based on the above information, Zee.Aero request s a minimum 5

- minute fuel reserve. This

would , according to the petitioner, allow time for contingencies such as loitering for traffic and at least one go around.

Public Interest

Zee.Aero states that its company is leading the development of new technolo gies to advance the safety, capability, user

- friendliness and public acceptance of personal aircraft. The results

of this work , Zee.Aero believes, will confirm that the technologies are via ble and can benefit the public and lead to a higher level of safet y and increased accessibility to the benefits of personal flight than is currently available with traditional General Aviation aircraft.

A summary of the petition was published in the Federal Register on December 12, 2014, ( 79 FR 75610 ). No comments were received.

The FAA’ s analysis is as follows:

The FAA agrees with the petitioner that alternative methods of propulsion would serve the public interest by reduc ing or eliminat ing consumption of traditional fuels, providing a more

cost effective and environ mentally friendly benefit to personal flight. However, the FAA

believes that Zee.Aero does not substantiate the necessity of a grant of exemption to conduct flights in electric, battery powered aircraft without the minimum fuel reserve for day VFR flight

.4

Zee.Aero is not unique in that electric, battery powered aircraft currently operate worldwide. European designs include battery powered electric motor

- gliders, as well as single and multiengine aircraft. Unmanned Aircraft System (i.e. drone) aircraft a lso utilize non

- fueled, electric motors with battery power. As an example, GreenWing International designs an experimental, amateur built aircraft with battery powered electric motors that meet s the requirements of Section 91.151(a)(1). Additionally, Aer o Electric Aircraft Corp (AEAC) has developed a solar

- electric powered aircraft

. The AEAC Sun Flyer airplane is currently

involved in initial R& D flight test operations at Centennial Airport near Denver, CO. These

non

- fuel operated aircraft do not requ ire an exemption from Section 91.151(a)(1) because they operate with the VFR 30 minute reserve required by regulation.

The petitioner states that the request for a lower fuel reserve is based on endurance restrictions due to the significant weight penal ty of currently available battery systems

. The petitioner’s reasoning that weight l imitations prevent longer su stained flight is insufficient for the FAA to grant an exemption. S imilar airplanes have conducted R&D flight operations without relief

from 91 .151(a)(1).

The FAA notes that the airfield chosen by Zee.Aero, Inc. for R&D flight tests has significant general aviation flight activity a ccording to information displayed in the U.S. & Territories Airport Lookup on the FAA.gov website ( https://nfdc.faa.gov/nfdcApps/airportLookup/index.jsp?category=null ) as well as

AeroNav.Com

. AeroNav.com displays the follo wing operational statistics for a 12

- month period ending 12 Au gust 2014 :

Aircraft based on the field: 178 Single engine airplanes: 99 Multi engine airplanes: 7 Jet airplanes: 5 Helicopters: 2 Gliders airplanes: 45 Ultralights: 20

Aircraft operations: avg 144/day

57% local general aviation

41% tr ansient general aviation

2% military

General Remarks:

• MODEL ACFT CLUB CONDUCTING FLT OPNS 3 MILES WNW OF ARPT

HEADING OF 290 DEGREES FM ARPT SURFACE TO 500' AGL.

• CAUTION

- WATCH FOR FIRE FIGHTING ACFT JUNE THRU OCTOBER5

.

• GLIDER ACTIVITY ON AND INVOF ARPT.

The petitioner did not submit a plan to communicate their R&D activities to non

- participating

aircraft nor did they submit a substantial risk mitigation plan designed to minimize exposure

to non

- participating aircraft.

The FAA’s Decision:

In considerati on of the foregoing, I find that a grant of exemption would not provide a level of safety at least equal to that provided by the regulations

. Therefore, pursuant to the authority

contained in 49 U.S.C. §§ 106(f), 40113 and 44701

, delegated to me by the Ad ministrator, the petition of Zee.Aero Inc. for an exemption from 14 CFR § 91.151(a)(1) is hereby denied.

Issued in Washington, D

. C

. , on April 13, 2015.

.

//s//

John S. Duncan Director, Flight Standards Service