AFS-13-481-E

Exemption No. 10779A

UNITED STATES OF AMERICA

DEPARTMENT OF TRANSPORTATION

FEDERAL AVIATION ADMINISTRATION

WASHINGTON, DC 20591

 

In the matter of the petition of 

 

DESERT AEROSPACE, LLC Regulatory Docket No. FAA-2012-0970

 

for an exemption from § 61.58

of Title 14, Code of 

Federal Regulations 

 

DENIAL OF PETITION FOR RECONSIDERATION

By letter received July 22, 2013, Mr. Robert Carlton, Desert Aerospace, LLC, (Desert 

Aerospace), 604 Newport Court SE. Albuquerque, NM 87123 petitioned the Federal Aviation 

Administration (FAA) for reconsideration of Denial of Exemption No. 10779, dated May 24, 

2013. In its Denial of Exemption No. 10779, the FAA had found that relief from annual 

proficiency check requirements for pilot(s) of Desert Aerospace turbojet-powered Comp-Let 

TST-14 (TST-14) glider was not in the public interest.

The petitioner requests relief from the following regulation:

Section 61.58(a) prescribes, in pertinent part, that to serve as pilot in command of an aircraft 

that is type certificated for more than one required pilot flight crewmember or is turbojetpowered, a person must--

(1) Within the preceding 12 calendar months, complete a pilot-in-command 

proficiency check in an aircraft that is type certificated for more than one 

required pilot flight crewmember or is turbojet-powered; and 

(2) Within the preceding 24 calendar months, complete a pilot-in-command 

proficiency check in the particular type of aircraft in which that person will 

serve as pilot in command that is type certificated for more than one required 

pilot flight crewmember or is turbojet-powered.

The petitioner supports its request for reconsideration with the following information:

The petitioner provided three general reasons as the bases to petition the FAA for 

reconsideration of Denial of Exemption No. 10779. 
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1) The petitioner claims there are significant new facts, which were not presented in the 

original petition for exemption.

The petitioner notes that, since the denial of its petition, it has made modifications to the 

TST-14’s systems. Specifically, the petitioner has added a more capable auxiliary fuel pump 

which has eliminated the need to reduce throttle 20 seconds after initial climb due to the risk 

of engine ‘flameout.’

1 Petitioner contends that these modifications further simplify operation 

of the aircraft and may address certain concerns noted in the FAA’s denial of exemption.

The petitioner also notes that it has created a cockpit procedures trainer (CPT) that it uses for 

familiarizing pilots who do not have experience with any engine systems to the cockpit 

controls. Petitioner contends that the CPT would provide students training on the proper use 

of controls and best practices with regard to the aircraft and engine. The petitioner notes that 

pilots will have additional training because the TST-14’s operating limitations require an 

experimental aircraft authorization to act as pilot in command which petitioner currently 

conducts under a training syllabus approved by the FAA. Petitioner contends that this 

additional training would account for any perceived ‘differences’ of this aircraft to other 

motorgliders.

2) The petitioner stated the FAA made important factual errors in the denial of exemption

regarding the operational characteristics of the TST-14 and other turbojet powered 

aircraft.

Specifically, petitioner argues that the FAA failed to provide evidence of the TST-14’s 

operational characteristics common to turbojet-powered aircraft or the differences of the 

TST-14 and conventional motorgliders. Petitioner maintains that the FAA merely made an 

ambiguous reference to the petitioner’s website without providing specific references to the

significant differences inherent to the turbojet-powered TST-14.

The petitioner claimed the FAA made a contradictory argument by referencing that the 

requirement for “pilots... [to] comply with § 61.58 is not dependent on the performance of a 

particular aircraft, or similarities to piston-powered aircraft”; and then the FAA states that 

“pilots...must receive annual proficiency checks to ensure their continued understanding of 

the unique operating characteristics common to turbo-jet powered aircraft.” The petitioner 

also challenged the FAA multiple times to state specifically what characteristics its

turbojet-powered aircraft shared with other turbojet-powered aircraft that would justify an 

annual proficiency check.

The petitioner continued stating: “The operating speeds of the TST-14 closely mimic other 

motorgliders. Its best climb and approach speed of 65 knots is consistent with other 

 1 Flameout: An instance of the flame in the combustion chamber of a jet engine being extinguished, with a 

resultant loss of power © 2014 The Oxford University Press, Oxforddictionaries.com.
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motorgliders. Its Vne speed of 115 knots is similar to other gliders. Its flight controls are 

identical to those of other motorgliders. It has fixed gear, no flaps and no hydraulic systems.”

A reference to an FAA aircraft certification Advisory Circular; AC 23.1309-1E, 15 (g), is 

included by the petitioner as an example it feels presented “relaxed standards for turbo-jet 

aircraft which have performance more closely resembling conventional piston-powered 

aircraft.”

Notwithstanding the petitioner’s claims that the FAA failed to identify operating 

characteristics in the TST-14 that are similar to turbojet-powered airplanes, the petitioner 

noted that it holds a letter of deviation authority (LODA) to provide training under an 

FAA-approved training syllabus which would address any perceived “differences” that exist 

between the TST-14 and other motorgliders. 

3) The petitioner stated the FAA did not correctly interpret the intent of the rule. 

Petitioner renews its argument from the original petition that the FAA incorrectly interpreted 

the rule which petitioner argues was not intended to apply to all turbojet aircraft only turbojet 

airplanes.

The petitioner stated, “While the actual deliberative process will probably never be disclosed, 

the denial letter stated that it was always FAA’s intention to include gliders in the rule. Based 

on the reasoning presented in the denial letter, the petitioner believed the FAA’s reasons for 

denial demonstrate an incorrect interpretation of the intent of the rule.”

The petitioner asserted the FAA presented a circular argument that “an exemption to a rule is 

not possible because of the rule.” The petitioner elaborated on this sentiment by explaining 

that, “while we [the petitioner] cannot dispute that the rule, as written, does not take nonturbine-like performance into account, we [the petitioner] maintain that this lack of 

recognition of a special circumstance is the sole reason for this petition for exemption.”

The petitioner further stated:

FAA disagrees with our original statements regarding the use of the word ‘airplane’

vs. ‘aircraft’ (Note that our position on this was modified in January 2013, via the 

FAA docket website). FAA admits that the word ’airplane’ was used in the 

“Summary Table” and “Description of Proposed Changes” sections of the NPRM, but 

notes that the word ‘aircraft’ was used in the “Proposed Amendment” section and the 

final rule. FAA implied that the intent throughout the process was to include gliders. 

FAA further implies that since no description of the change from ‘airplane’ to aircraft’ 

was written, one should understand that the use of the word ‘airplane’ was 

unintentional. FAA further states that “the exemption process is not an appropriate 

mechanism to petition for rule change.” We remind FAA that it has a legal burden to 
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clearly state the scope of any new regulatory action. The use of the word ‘airplane’ 

(which specifically excludes gliders) in the portions of the NPRM that are likely to be 

read first (Description of Proposed Changes & Summary Table), even if the word 

‘aircraft’ is used in the official wording later, clearly constitutes a violation of that 

burden, and creates a situation whereby a reasonable person could draw the wrong 

conclusion as to the scope of the proposed rule. We disagree that the wording was 

corrected in the final rule. While the text of the final rule does use the word ‘aircraft’; 

the final rule summary table, as published in the Federal Register (Vol. 76, No. 169 / 

Wednesday, August 31, 2011 / Rules and Regulations, p54096) still uses the word 

‘airplane.’ Despite FAA’s inference that gliders were intentionally included, we 

seriously doubt that anyone involved in this rulemaking ever considered the impact of 

this rule on turbine powered gliders, and we invite FAA to provide records of any 

deliberative process where turbo-jet powered gliders were considered. This being 

said, we agree that the wording discrepancy involves a rule change, and therefore 

should be taken up in a forum other than the exemption process.

In the denial of exemption No. 10779 the FAA stated that § 61.58(d)(5) provides a number of 

ways for a pilot in command to accomplish a proficiency check. The petitioner stated that 

most pilots who have flown, or will fly, this aircraft do not fly other turbo-jet aircraft, and 

may not even hold an airplane rating. Therefore, the proficiency check will be conducted in 

this aircraft, in accordance with § 61.58(d)(5)(i), for the vast majority of pilots who will fly 

the TST-14. The petitioner elaborated stating:

FAA’s implication that it should avoid the burden of § 61.58 by simply not utilizing 

the second seat is outrageous. FAA stated “§ 61.58(e) provides an exception ... by 

only requiring compliance when carriage of persons is involved.” We also recognize 

that the requirement for yearly proficiency check only applies to pilots who intend to 

carry passengers. However, we do not recognize that this fact has any bearing on this 

petition. We did not incur the additional expense of a two seat aircraft with the 

intention of flying with one seat empty. To the extent allowed for experimental 

aircraft, the second seat is an asset we intend to utilize.

4) The petitioner stated that the FAA’s public interest analysis was incorrect

The petitioner states the FAA’s analysis was incorrect, claiming:

While it is true that as of this writing, only three persons are checked out in the 

TST-14, we disagree with FAA’s logic as it applies to safety as a benefit to the public. 

It is not relief from the additional burden on the three current pilots that benefits the 

public. It is the potential future users of this technology who will benefit.
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The FAA's analysis is as follows:

Overall, the petitioner’s statements reflect the requirements of 14 CFR § 11.101 for 

reconsideration of its petition.

Petitioner’s claims regarding additional significant facts.

The FAA agrees the petitioner has improved the fuel system of its TST-14 turbojet-powered 

aircraft. However, by emphasizing this fact, the petitioner provides an example of a situation 

‘flameout,’ that is common to other turbojet-powered aircraft as well. This condition is not 

present in piston-powered aircraft. While this new system may provide increased safety 

beyond the scenario presented in the original petition, it also reinforces that the petitioner’s 

TST-14 turbojet-powered motorglider possesses unique operating characteristics common to 

turbojet-powered aircraft, and thus the aircraft fits within the rationale for imposing the 

requirement for a recurrent proficiency check. See Pilot in Command Proficiency Check and 

Other Changes to the Pilot and Pilot School Certification Rules, 76 FR 54095, 54098 

(Aug. 31, 2011).

With regard to the CPT offered by the petitioner, the FAA sees this training as a tool to assist 

in the training of pilots unfamiliar with engine systems. Although the FAA supports the use 

of training aids, the petitioner has failed to show how the CPT would ensure a pilot’s 

proficiency on a recurring or annual basis as required by 61.58.

The petitioner correctly acknowledges the TST-14’s operating limitations require a pilot to 

possess an experimental aircraft authorization to act as pilot in command. This limitation is 

contained in the operating limitations that are a part of the aircraft’s Special Airworthiness 

Certificate. The “NOTE” described in FAA Order 8130.2F, which was in effect when the 

certificate was issued, states in pertinent part that:

NOTE: This limitation applies to any turbojet/turbofan-powered aircraft, any aircraft 

with a maximum takeoff weight exceeding 12,500 pounds, and any other aircraft when 

deemed necessary.

All turbojet-powered aircraft with this limitation require that the pilot possess an experimental 

aircraft authorization to act as pilot in command. Therefore, all pilots required to possess 

such an authorization are also required to comply with the 14 CFR § 61.58 annual proficiency 

check requirement.

The FAA disagrees with the petitioner’s belief that the ratio of pilots to the one current FAA 

inspector is burdensome. At the time of Denial of Exemption 10779, there were three airmen

who possessed TST-14 experimental aircraft authorizations; presently there are six airmen. 

FAA inspectors and experimental aircraft examiners (EAEs) currently provide similar 
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services to a ratio of many more airmen than exist in the case of the TST-14. As with any 

certification activity, as the number of airman applicants increase and there is a need for 

additional qualified inspectors or EAEs, the FAA designates additional resources to provide 

those services.

Petitioner’s claims of factual error regarding the operating characteristics of the TST-14

Contradictory Statements about Operating Characteristics

The FAA disagrees with the petitioner’s belief that the following statements are contradictory:

[T]he requirement for pilots...to comply with § 61.58 is not dependent on the 

performance of a particular aircraft, or similarities to piston-powered aircraft; and

during the discussion of the final rule which states in part “pilots...must receive 

annual proficiency checks to ensure their continued understanding of the unique 

operating characteristics common to turbo-jet powered aircraft”

A turbojet-powered aircraft may perform better or worse than its piston-powered counterpart,

yet that aircraft will fundamentally have unique operating characteristics common to turbojetpowered aircraft. One such characteristic emphasized by the petitioner provides an example 

that is common to turbojet-powered aircraft - ‘flameout’. This condition is not present in 

piston-powered aircraft. Furthermore, the discussion of unique operating characteristics 

common to turbojet-powered aircraft mentioned in the Denial of Exemption No. 10779 comes 

directly from the preamble to the final rule Pilot in Command Proficiency Check and Other 

Changes to the Pilot and Pilot School Certification Rules, 76 FR 54095, 54098 (Aug. 31, 

2011). That section discusses that the passenger carrying capability is what requires 

confirmation of a pilot’s ability to operate safely in a turbojet-powered aircraft. An excerpt

from that section states:

the FAA firmly believes that pilots conducting flight in turbojet-powered experimental 

aircraft with more than one seat, who wish to carry a passenger, must receive annual 

proficiency checks to ensure their continued understanding of the unique operating 

characteristics common to turbojet-powered aircraft. An experimental jet aircraft that 

by original design or through modification possesses more than a single seat, has the 

potential to carry one or more passengers. In such a case, the pilot will be directly 

responsible for those passengers. We believe these circumstances demand a higher 

level of confirmation of the pilot's ability to operate safely in a turbojet- powered 

aircraft.

Petitioner’s reliance on AC 23.1309-1E, 15(g), as an example of relaxed standards for turbojet 

powered aircraft is misplaced. That AC concerns applicants seeking issuance of a Type 

Certificate, an Amended Type Certificate, a Supplemental Type Certificate, or a Parts 
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manufacturing Approval for the initial approval of the new type design or a change in the 

approved type design. The AC does not address proficiency checks, which is the subject of 

this petition. Specifically, the example referenced in paragraph 15(g) discusses conditions in 

which an airplane having a Single Turbine Engine, that would normally be considered a 

Class II airplane according to Figure 2, could be treated as a Class I airplane. Paragraphs 

15(a), (b) and (c) and Figure 2 of AC 23.1309-1E explain that the class of airplane

corresponds to assigned numerical values concerning probability of system failures based 

upon similar, historic data of software and complex hardware installations. Additionally, the 

AC 23.1309-1E, 15(g) reference presented by the petitioner only applies to “airplanes”

certificated in the standard category. Regardless, a turbojet-powered airplane which may be 

classified as Class I for certification purposes would still require that the pilot in command 

meet the § 61.58 proficiency check requirement. 

References to the Petitioner’s Website

The petitioner is correct that the FAA did not elaborate on the specific references to the 

petitioner’s website (www.desertaerospace.com) researched in Denial of Exemption 

No. 10779. In that denial, the FAA stated that the “petitioner’s website discusses significant 

differences inherent to the turbojet-powered TST-14.” In addition to the “superior 

performance” items listed by the petitioner, the FAA’s original statement also pertains to the 

four-day course that the petitioner offers to obtain a “Jet Glider Rating.” In particular, the 

petitioner’s website uses the term “similar” (and still does) in the following way:

Upon completion of an evaluation with a qualified airman, you will be issued a rating 

for the TST-14 jet sailplane. This rating will appear on your pilot certificate (similar 

to a jet airplane type rating).

That original reference, in its entirety, stated the following:

Jet Glider Rating - Our FAA-approved training program features ground, systems and 

flight training to obtain a jet glider rating. It is also recognized by sailplane insurance 

carriers. The four day course includes 8 hours of ground training and 8 hours of flight 

training. It covers all aspects of jet sailplane operation. Here's a sample of the 

training syllabus:

Section 1 - Ground Training

General Overview

TST-14J Flight Manual

PBS TJ-100 Operations and Maintenance Manual

Extension/Retract Mechanism (ERM)

Fuel System

Fueling/defueling
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Front Cockpit Checkout

Pre-flight Checklists

Engine Controls, Display, Ground Starting, Shutdown

Self-launching

Transitioning into unpowered flight (in-flight shutdown & retract)

Transitioning to Powered Flight (In-flight extension and restarting)

Landing with power

Post-flight Checklists

Section 2 - Flight Training

Normal Soaring Flight (Self-launch, shutdown, retract, land no power)

Flight with restart (Self launch, shutdown, retract, restart, land w/power)

Pattern Practice (Multiple takeoffs, shutdown, retract, land no power)

Advanced Training (Solo preparation – Patterns, emergency procedures)

Upon completion of an evaluation with a qualified airman, you will be issued a rating 

for the TST-14 jet sailplane. This rating will appear on your pilot certificate (similar to 

an a jet airplane type rating). This course also counts as a BFR. 

Cost $2850

With regard to the petitioner’s LODA, the TST-14 was issued a special airworthiness 

certificate in the experimental exhibition category for the purpose of operating exhibition & 

air racing category aircraft. Pertinent parts of 14 CFR § 91.319 state:

No person may operate an aircraft that has an experimental certificate for other than 

the purpose for which the certificate was issued. The FAA may issue deviation 

authority providing relief from the provisions of paragraph (a) of this section for the 

purpose of conducting flight training. The FAA will issue this deviation authority as a 

letter of deviation authority.

The LODA provides the means by which the petitioner is permitted to offer its specialized 

TST-14 training program. However, as the FAA stated previously, the nature of the relief 

sought by the petitioner is not from a training requirement; the petitioner seeks relief from a 

recurrent check of a pilot’s proficiency. The petitioner has not sufficiently described how use 

of the training program would provide an equivalent level of safety to assessing a pilot’s 

proficiency on a recurring or annual basis.

FAA’s interpretation of the rule and public interest determination. 

Regarding the petitioner’s belief that the FAA incorrectly interpreted the intent of the rule or 

presented a circular argument, the FAA disagrees. The petitioner claims that the FAA 
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somehow implied in Denial of Exemption No. 10779 that “an exemption to a rule is not 

possible because of the rule.” An exemption is what the petitioner requested; that process is

evaluated by the criteria set forth in 14 CFR § 11.81. The FAA based Denial of Exemption 

No. 10779 on that analysis. A petition to amend a rule is evaluated by different criteria set 

forth in 14 CFR § 11.71. Furthermore, the petitioner states, “we [the petitioner] agree that the 

wording discrepancy involves a rule change, and therefore should be taken up in a forum 

other than the exemption process.” The reference (which is two separate, sequentially 

occurring paragraphs) in Denial of Exemption No. 10779 is repeated here in its entirety:

Regarding the petitioner’s statements that the use of the word “aircraft” in § 61.58 was 

inadvertent, the FAA disagrees. Although the “Summary Table” and “Description of 

Proposed Changes” sections in the Notice of Proposed Rulemaking (NPRM) 

referenced by the petitioner (Docket No. FAA-2008-0938; Notice No. 09-08) 

incorrectly used the word “airplane”, the “Proposed Amendment” section containing 

the draft regulatory text used “aircraft” with regard to proposed changes to § 61.58. 

The Final Rule issued after the NPRM also used “aircraft” in the same manner, 

consistent with the requirements of § 61.58 prior to issuance of the NPRM. 

Additionally, the Final Regulatory Evaluation considered the impacts of the change on 

aircraft, not airplanes. Furthermore, the NPRM did not describe proposed impacts of 

changing the requirement from “aircraft” to “airplane” and the result is that the current 

rule continues to use the term “aircraft” as it had in previous versions of § 61.58.

Regarding comments submitted in support of changing the rule to revise applicability 

to “airplanes” only, the FAA notes that the exemption process is not an appropriate 

mechanism by which to petition for a rule change.

The FAA affirms its original statement that the NPRM did not describe proposed impacts of 

changing the requirement from “aircraft” to “airplane” and the result is that the current rule 

continues to use the term “aircraft” as it had in previous versions of 14 CFR § 61.58. The 

FAA agrees with the petitioner that the final rule summary table referenced by the petitioner 

does repeat that same incorrect reference to “airplane” in the same manner as the NPRM. 

The FAA disagrees with petitioner that the FAA implied that the “burden” of the 

14 CFR § 61.58 proficiency check could be avoided by not utilizing the aircraft’s additional 

seat. The rule provides other applicable circumstances that would satisfy the 14 CFR § 61.58

proficiency check requirement in pertinent parts of § 61.58(d)(5). As with other experimental 

aircraft, a proficiency check in the particular aircraft is not the only way in which to satisfy 

the requirement. Additionally, the rule allows for operation of the aircraft if no carriage of 

passengers is involved. These are factual statements, with no implication about avoiding a 

regulatory requirement. The utilization of the petitioner’s additional seat in the TST-14 is not 

limited if the pilot in command is in compliance with the 14 CFR § 61.58 pilot-in-command 

proficiency check requirement.
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The FAA stated in Denial of Exemption No. 10779 and again affirms that the petitioner has 

not sufficiently described how relief from a requirement to ensure a pilot’s proficiency would 

provide an equivalent level of safety or benefit the public as a whole. The petitioner feels that 

this “regulatory burden” will discourage potential future users of this technology. The 

implication is that an annual 14 CFR § 61.58 pilot-in-command proficiency check 

requirement could hinder the popularity or growth potential of this technology. The FAA has 

determined, as in Denial of Exemption No. 7693 (World Balloon), that popularity itself is not 

a public benefit. The FAA notes that there are a significant number of popular activities that 

do not benefit the public, but are, in fact, detrimental to the public. The benefit to the public 

interest must be set forth definitively and explicitly. 

The FAA’s Decision

In consideration of the foregoing, I find that a grant of exemption is not in the public interest. 

Therefore, pursuant to the authority contained in 49 U.S.C. §§ 40113 and 44701, the petition 

of Desert Aerospace, LLC for reconsideration of Denial of Exemption No.10779 from 

14 CFR § 61.58 to permit relief from annual proficiency check requirements for pilot(s) of 

their turbojet-powered TST-14 glider is hereby denied.

Issued in Washington, D.C. on May 1, 2015. 

//s//

Michael P. Huerta

Administrator