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In the matter of the petition of Desert Aerospace, LLC for exemption from certain portions of § 61.58 of Title 14, Code of Federal Regulations (Exemption No. 10779

– Docket No. FAA

- 2012

- 0970) , dated September 5, 2012. **Petition for reconsideration of denial**  We have received a letter of denial, dated May 24, 2013. Inaccordance with the 14 CFR §11.101, we hereb y petition FAA for reconsideration of this denial based on the following: 1. We have additional significant facts, which were not presented in the original petition for exemption. Some of these facts are the result of modifications to the systems of the aircraft in question, which were accomplished after the initiation of the original petition. These modifications further simplify the operation of the aircraft, and may address certain concerns FAA noted in the denia l letter. Some facts were not presented due to the unclear wording of the rule, and are being presented below in response to FAA statements in the denial letter. 2. FAA made important factu al errors in the denial of our petition. FAA’s use of general references, such as “the petitioner’s website”, without citing the specific concerns regarding the differences between the operation of this aircraft and other similar aircraft , or similarities to turbojet powered aircraft, are ambiguous. FAA’s use of a circular reference argument is questionable

. 3. FAA did not correctl y interpret the intent of the rule. While the actual deliberative process will probabl y never be disclosed, the denial letter states that it was alway s FAA’s intention to include gliders in the rule. Based on the reasoning presented in the denial letter, we believe that FAA’s reasons for denial demonstrate an incorrect interpretation of the intent of the rule. **FAA summary of pe tition request**  FAA’s summary

of our initial petition for exemption and initial support information is essentially

correct. FAA’s summary of comments is essentially correct. **FAA’s analysis General**  FAA’s statements regarding the registration number, serial number, operation, general description of the aircraft in question (hereinafter referred to as the TST

- 14 ) as a ‘turbo

- jet powered motorglider’ and definition of a glider, per 14 CFR § 1.1, are ess entially correct. **Recognition of application**  **of** § **61.58 to gliders** FAA notes that “even though this glider does not depend principall y on an engine for free flight, it remains a turbo

-

jet powered aircraft”. We rec ognize that that the TST

- 14 is a turbo

- jet powered aircraft, and thus is subject to 61.58, or else there would be no need to petition for an exemption. **Methods of compliance with §**  **61.58** FAA states that “§ 61.58(d)(5 ) provides a number of way s for a pilot

- in

- command to accomplish a proficiency

check”. However, we note that most pilots who have flown, or will fly , this aircraft do not fl y other turbo

- jet aircraft, and may not even hold an airplane rating. For the vast majority of pilots who will fly the TST

- 14 , the proficiency check will be conducted in this2

aircraft, IAW § 61.58(d)(5)(i). We also note that, as of this writing, onl y one person (an FAA inspector) has been approved by FAA to provide proficiency checks i n the TST

- 14

. FAA states that “§ 61.58(e) provides an exception ... by onl y requiring compliance when carriage of persons is involved”. We also recognize that the requirement for y earl y proficiency check onl y applies to pilots who intend to carry passenge rs. However, we do not recognize that this fact has an y 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 secon d seat is an asset we intend to utilize. FAA’s implication that we should avoid the burden of § 61.58 b y simply not utilizing the second seat is outrageous. **Rule wording (Airplane vs. aircraft)** 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 states that the word ‘aircraft’ was used in the “Proposed Amendment” section and the final rule. FAA implies 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 they have a legal burden to clearl y state the scope of an y new regulatory action. The use of the word ‘airplane’ (which specificall y excludes gliders) i n 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, clearl y constitutes a violation of that burden, and creates a situation whereb y 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 ru le does use the word ‘aircraft’; the final rule summary table, as pub l ished 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, w e seriously

doubt that an yone involved in this rulemaking ever considered the impact of this rule on turbine powered gliders, and we invite FAA to provide records of an y deliberative process where turbo

- jet powered gliders were consider ed. Thi s being said, we agree that the wording discrepancy involv es a rule change, and therefore should be taken up in a forum other than the exemption process. **Propulsion type, performance characteristics**  FAA states 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”. Indirect contradiction of this statement, FAA goes on to cite 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 ” . While we cannot dispute that the rule, as written , does not take non - turbine

- like performance into account, we maintain that this lack of recognition of a special circumstance is the sole reason for this petition for exemption. FAA’s argument that ‘ an exemption to a rule is not possible because of the rul e’ is a circular reference argument that in essence undermin es the entire exemption process. We also point out that FAA does recognize relaxed standards for turbo

- jet aircraft which have3

performance more closely resembling convent ional piston

- powered airc raft (and vice versa) . AC 23.1309

- 1E, (15)(g) states:
“

... in part 23, turbine

- engine airplanes traditionally have been subject to more stringent requirements than a single

- engine reciprocating airplane. A single

- engine reciprocating airplane generally

has a wider stall

- cruise speed ratio than traditional turbine

- en gine airplanes. Such an airplane with a stall speed under 61 knots with simple sy stems, and **with otherwise similar characteristics to a traditional single -**  **engine reciprocating airplane (except for a higher cruise speed and a more reliable engine that is si**  **mpler to operate), can be treated as a Class I airplane under this analysis**  . Conversel y, if a single

- engine reciprocating airplane has the performance, mission capability, and s ys tem complexity

of a higher class (such as cabin pressurization, high cruise a ltitude, and extended range), then that ty pe of airplane design may align itself with the safet y requirements of a higher class (for example, Class II airplane). These determinations should be made during the development of the certification basis.” (Empha sis ours) W e also disagree that the TST

- 14 possesses an y “unique operating characteristics common to turbo

- jet powered aircraft”, and no characteristics that are complex or which require skills that need to be monitored annually

. FAA further rationalizes the denial, citing “significant differences in performance and capabilities of turbojet powered aircraft (including gliders) when compared to that of similar piston

- powered aircraft ” . FAA further states, ambiguousl y, that “the petitioner’s website discus ses significant differences inherent t o the turbo

- jet powered TST

- 14 ” . We strongl y disagree that such significant differences exist to the extent that they would need to b e monitored annually . Also, please note that websites used for sales purposes will contain superlatives. Does the Cessna 182 website not make claims of superior performance to other similar aircraft? A search of our website ( www.desertaerospace.com ) for such statements produced the following: 1. “ The [TST

- 14’s] climb far exceeds an y other motorglider we have compared with (Stemme, DG

- 505, ASH

- 26E). ” 2. “ Two switches control all engine extend/retract/start functions. They are simply

' Pylon' (up/down) and 'Engine' (run/stop). Door actuatio n is handled automaticall y by a door/pylon sequencer when pylon commands are actuated. ” 3. “ A cooldown period of about 2 minutes is required after shutdown before retracting the engine. Engine retract may be commanded at any

time after engine shutdown. The pylon/door sequencer will automatically take care of cooldown timing. ” 4. “ The jet engine is extremely simple, and at 42 pounds, it is only about 1/3 the weight of equivalent piston engines. ” 5. “ It[the turbojet engine] does not require any belt drives, speed red

ucers or massive pylons. It requires very

little input from the pilot for starting , and does not require any prop positioning or 'bumping' for retraction. ” 6. “ When extended, the jet engine has about the same drag as a single Cessna 172 wheel pant. ” 7. “ The jet engine also produces almost no vibration, eliminating the most significant cause of cracking and fatigue failures in all aircraft s ys tems, including the structure and avionics. ”4

8. “ Also looming on the horizon is the elimination of 100LL (leaded) avgas. The BonusJe t uses jet fuel, which does not contain lead. ” 9. “ Ithas a much higher cruise speed than most other motorgliders, allowing it to reach good soaring conditions a fair distance from the takeoff point. ” 10. “ We routinely

launch mid

- field with two persons while some other motorgliders are waiting for a tow, unable to self

- launch in the hot & high conditions. The BonusJet's takeoff requirements are considerabl y better than any other motorglider we have compared with (Stemme, DG

- 505, ASH

- 26E). We challenge FAA to state specifically which of the statements above , is a “unique operating characteristic common to turbojet powered aircraft” that justifies an annual proficiency check. Is it the exceptional climb rate, which being significantly better than most motorgliders, provides a safe altitude margin during climb, while most other motorgliders are still dodging telephone poles 1⁄2 mile off the end of the runway? I s it the two switches that control all engine and pylon functions, as opposed to the manual doors, propeller stops, manual door locks, propeller position
‘ bumping ’ , chokes, primers and compression releases found on most motorgliders? I s it the automatic cooldown cycle, instead of the t ypical m anual cooldown that requires partial retraction of the engine first? Is it the turbine engine’s light weight and simplicity? I s it the turbine engine’s low drag when extended? Does handling jet fuel require special skills compared with 100LL or the auto fuel/oil mix required for two cycle engines ? Recognizing that man y pilots who may wish to fl y the TST

- 14 may not be airplane pilots, and therefore not familiar with any engine s ys tems, we created a cockpit procedures trainer (CPT), which we use for familiarizing new pilots with the cockpit controls. A version of the CPT may be accessed from our website. This tool was designed for use with instructor supervision, and contains some highl y exaggerated warnings and errors. For example, l eaving the master switch on for 20 seconds with no commands will trigger the ‘dead battery ’ warning. Holding the engine retract over
- ride switch with a hot engine will produce a ‘fire’ warning. Maintaining the thro ttle at 100% for 20 seconds produces a ‘flameout’ warning. None of these will happen in reality , but the visual cues will remind students of the proper use of controls and best practices with our aircraft and engine. (Note: The recent addition of a more capable auxiliary fuel pump has eliminated the need to reduce throttle after initial climb.) Again, we challenge FAA to state specifically which of these items is a “unique operating characteristic common to turbojet powered aircraft ” , which justifies an annual proficiency check. The two switches that control all engine and p yl on functions? The simple automatic start sequence? The automatic door sequencing? The CPT also includes an instrument panel tour. A review of the instrument panel shows mostly common glider instruments , such as altimeter, ASI, variometer (sensitive rate of climb indicator used for soaring) , radio, di gital fuel quantit y, volts, H obbs an d a mirror ( allows the pilot to see the engine and door position). The digital engine display features LED scales for engine RPM & EGT, and (idiot light) indictors for generator and oil pressure. A single indicator lamp provides pylon status (off = down, on = up, fast blink = in motion and slow (tick tock) blink = retract commanded, cool

- down timer active).5

Once again, we challenge FAA to state specifically which of these items is a “unique operating characteristic common to turbojet powered aircraft” , which justifies an annual proficiency check. The mirror, perhaps? The operating speeds of the TST

- 14 closel y mimic other motorgliders. Its best climb and approach speed of 65 knots is consistent with other motorgliders. Its Vne speed of 115 knots is sim ilar to other gliders. Its flight controls are identical to those of other motorgliders. Ithas fixed gear, no flaps and no hydraulic s ys tems. Once again, we challenge FAA to state specifically which of these items is a “unique operating characteristic common to turbojet powered aircraft ” , which justifies an annual proficiency check. The 65 knot best climb speed? The 115 knot Vne ? Most jets will not even lift th e nose wheel at these speeds. Is i t the lack of retractable gear, flaps and hydraulics? F AA states that “FAA data indicates that only three airmen currentl y hold an experimental aircraft authorization to act as pilot in command of the TST

- 14. The petitioner has not demonstrated how the perceived “training burden” on these pilots will benefit the public”. 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. Itis not relief from the additional burden on the three current pil ots that benefits the public. It is the potential future users of this technology

who will benefit. The safet y record of piston

- powered motorgliders is far from stellar. The complexity of their engine sy stems, coupled with the general lack of reliability of two

- cycle engines (originally manufactured for yard work) and the high drag of the extended engine /propeller combination , has resulted in numerou s accidents. In stark contra st , the few turbine motorgliders currently flying with moder

n turbine engines have a perfect safet y record. We believe that equipping gliders with modern, aircraft

- qualit y turbine engines represents a vast improvement in safet y for glider pilots. Since most recreational glider pilots are not profes sional pilots, and therefore tend to balk at additional FAA checkrides, the additional regulatory burden (our use of the term ‘training burden’ in the original exemption was incorrec t ) does tend to drive them away fro m the turbine glider concept. We have had numerous calls from pilots interested in flying (or bu yi ng) the TST

- 14 , who decline when they learn that the TST

- 14 requires an annual FAA checkride. Rel ief from this regulatory burden, which can involve substantial time and coordination with the single FAA inspector allowed to perform this function, would encourage more pilots to examine the turbine glider concept, thus not just maintaining an equivalent level of safet y, but actually improving the safet y of the sport. **TST -**  **14 Training Requirements** T he TST

- 14’s operating limitations do require an experimental aircraft authorization to act as pilot in command

. We hold a Letter of Deviatio n Authority (LODA) to provide transition training. Under the terms of the LODA, FAA recognizes our training s yl labus. So, anyone who acts as PI C in the TST

- 14 will have additional FAA approved training to account for any perceived ‘differences’ of this a ircraft to other motorgliders. Currentl y, only one person (an FAA inspector) has been authorized to conduct the checkride for this authorization.6

**Summary** FAA has, in essence, based their denial of our petition for exemption on four claims, as follows: 1. The TST

- 14 has “ unique operating characteristics common to turbo

- jet powered aircraft ” 2. The TST

- 14 is significantly different from traditional piston powered motorgliders in that it possesses “ significant differences in performance and capabilities of turbo jet powered aircraft (including gliders) when compared to that of similar piston

- powered aircraft ”. 3. “§ 61.58 applies to all turbojet aircraft (including gliders) 4. Due to the low number of pilots currentl y approved to fly the TST

- 14, the exemption, if grante d, provides no benefit to the public FAA has failed to provide specific examples in support of (1) and (2) above, only ambiguous references to “the petitioner’s website”. The TST

- 14’s low operating speeds and simple sy stems are similar to , or simpler than, those found on most other motorgliders, and are not in an y wa y similar to most other turbojet powered aircraft. FAA’s reasoning that an exemption to a particular rule cannot be granted because of that rule (3) is a ridiculous use of a circular referenc e argument, which, if true, undermines the intent of the exemption process. The exemption process exists to recognize specific cases for which the rule, though technicall y applicable, may not be appropriate. We believe the application of certain portions of § 61.58 to the TST

- 14 represent such a case. FAA’s argument that the low number of pilots currently rated to act as PI C of the TST

- 14 means there is no benefit to the public is not valid. The potential benefit of a simpler, more reliable method of la

unching gliders will benefit the entire soaring community . Any emerging technology

that improves safet y, and which has the potential to cross over to other small aircraft segments, represents a benefit to the public as a whole. Modern, small turbine engi nes are just such a technology

. I think it is safe to say

that historically , few single item s have contributed more to the safet y of a particular segment of aviation (airlines, helicopters, business aircraft) more than the introduction of reliable, vibration

- free turbine engines. In the past, there has alway s been a trade

- off between the safet y and reliability of turbine engines and the high speeds, high altitudes and complex sy stems required for su ch operations. This is no longer true. Small, reliable turbine engines can now operate at essentially the same speeds, altitudes and operating conditions as piston engines , with considerabl y simpler systems . Nowhere is this more easily demonstrated than in the sport of soaring, where launching b y means of a rope or tiny two
- cycle engine has alway s been one of the most critical (and dangerous) part s of the flight. The introduction of turbine engines to gliders will save lives! Any regulatory

burden that hinders the widespread acceptance of modern, aircraft quality

turbine engines in gliders will only serve to perpetuate these antiquated launch methods. In light of FAA’s failure to provide evidence of operational characteristics common to turbojet powere d aircraft, or differences to conventional motorgliders, w e hereb y request the FAA reverse the denial decision. May common sense prevail...