### Jean-Pierr

e Harriso n Pag e 1 o f 5 1183 5 Skyline Blvd
. r .^-r , .pM T n p I^atos,CA9503 3 '-^siwiO N 408/872-125 7 ' " ^ ' "" ' 6July201 1 .•i! ! JJ L ! ! A > 0 8 

### Petitio n t o Appl y FAR§91.119(d ) Minimu mSqf e AMtudes : General : HeUcapter s t o al l Rotorcraf

t Introductio n Thi s documen

t i s arefiling o f

m y earlie r petitio n Docke

t FAA-2009-083 8 whic h wa s denie db y th e Federa l Aviatio n Administratio n on 1 5 Decembe r 2010
. Saiddenia

l wa s base don grossl y incorrec t applicatio n and/or

interpretatio n o f

th e relevan

t Federa l Aviation Regulations , lack o f fundamenta

l understandin g o f

th e operatio n o f

rotary-win g aircraft , anda n obviou s prejudic e agains t gyroplane s a s a clas s o f aircraft
. Thi s refile dpetitio n i s update dt o accoun t fo r th e change s t o FA

R91.119 : Minimu

mSaf e Altitudes : General which cam e into effec

t afte r thi s petitio n wa s filed andwer e applicabl e eigh

t month s befor e th e dat e o f th e denia l o f m y origina l petition
. Copie s o f

m y origina l petition , th e Federa

l Aviation Administratio n denia

l letter , andm

y respons e t o sam

e ar e include da s supportin g doamientatio n t o thi s refiledpetition
. Explanatio n o f

Propose dActio n an dIt s Purpos e Ther e hav e historicall y bee

n thre e fimdamental type s o f rotorcraft : gyrodyne , gyroplane , andhelicopter , o f which th e latte

r tw o hav e been continually in servic e sinc e their inception
. Certificatio n an doperationa l regulation s fo

r helicopter s hav e been develope dan drefine dsinc e it s emeigenc e a s apractica l aircraf t an d currentiy reflec t

th e capabilitie s andlimitation s o f thi s clas s o f

aircraft
. The sam

e i s no t tru e fo r th e gyroplane s th e operatio n o f which ar e sometime s governe dby helicopte r regulation s andsometime s by airplane regulations. Gyroplane s hav e by andlarg e been historically regarde da s testbed s fo r rotary-win g development
. Successiv e model s o f

gyroplane s manufacturedby licensee s o f th e Cierv aAutogir

o Company , Ltd
. (Autogir o Compan y o f America , etc. ) each furtheredth e developmen t o f th e rotar y wing , witi i th e resul t tha t th e technolog y never

mature dunti l abou

t th e late 1930s
. Thi s rotary-win g technolog y wa s use di n th e first successful helicopter s such a s tiie Sikorsk y VS-300 , Sikorsk

y R-4 , Bell 47 , Kama

n K-225 , etc . Helicopte r developmen

t thereafte r displace dfUrthe

r gyroplan e efforts wit

h th e exceptio n o f

thre e FA A certificate dexample s o f

th e latte r (Ai r & Spac e 1 8 —FA

A Typ e Certificat

e 1H17 , Avia

n 2-18 0 —

FA A Typ e Certificat

e H5EA , McCuIloc

h J- 2 —FA

A Type Certificat

e H6WE ) to th e present . Thi s lack

o f attentio n ha s resulted in th e Federa l Aviation Regulation s becomin g ou t o f dat e wit h regardt o gyroplan e capabilities
. Th e purpos e o f

thi s petitio n i s to apply FA R§91.119(d) MinimumSaf e Altitudes : Genera

l t o all aircraf

t classe s withi n th e rotorcraf

t category , i.e
. gyrodyne , gyroplane , andhelicopter , fo r th e following reasons. 1 Appl y consistent

regulation s t o all aircraf

t classe s within th e rotorcraf t categor y when thos e aircraf

t posses s common capabilities
. 2 Remov e limitation s fromgyroplan e operation s which restric t th e usefulnes s o f

thi s clas s o f

aircraf t without providin g an

y increas e in safety
. 3 Recognitio n o f

th e resurgenc e o f

interes t i n anddevelopmen

t o f gyroplanes
. A

t th e time o f

writing , ther e are tw o well-funded , professionally manage dgyroplan e developmen t efforts (CarterCopters ,

### Jean-Pierr

e Harriso n Pag e 2 o f 5 1183 5 Skyline Blvd
. Lo s Gatos,C A 9503 3 US A 408/872-125 7 6 Jul y 201 1 www.cartercopters.co mandGroe n Brother s Aircraft , www.groenbros.co mi n additio n t o thos e develope dunde

r th e Ligh t Spor t Aircraf t Categor y (LSA ) certificatio n regulations. 4 Th e resurgenc e o f

interes t i n gyroplane s wa s recognize db y th e FA A b y it s inclusio n o f

adedicate d sectio n o n gyroplanes , comprisin g eigh t chapters , in th e 200 0 editio n o f Rotorcraf t Flyin g Handbook , FAA-H-8083-21 , fo

r th e first time in severa

l decades
. Propose dLanguag e fo r

Redefinitio n o f

FAR§91.119(d ) Mimmu mSt^eAMtudes : Genera l d) Rotorcraft
. Rotorcraf

t ma y b e operate da

t les s tha n th e minimum s prescribe din paragrap h (b ) or (c ) o f thi s sectio n if

th e operatio n i s conducte dwithout hazar dt o person s or

propert y o n th e surface
. I n addition , each perso n operatin g arotorcraf t shall comply wit

h an y route s or

altitude s specifically prescribe dfo

r rotorcraf t b y th e Administrator
. The ter mrotorcraf

t replace s th e origina

l ten n helicopter

in th e preceding
. Publi c Interes t

Serve db y th e Propose dActio n Th e publi c interes t

serve db y th e propose dactio n i s consistent regulatio n o f

al l aircraf t classe s withi n th e rotorcraf t categor y by eliminatin g unnecessar y altitud e limitation s whil e maintainin g safet y a t leas t a t curren t levels
. Th e purpos e o f

th e existin g regulation , FA R§91.119(d) Minimu

mSaf e Altitudes : General , i s t o permit helicopte r operation s a

t any altitude providin g hazardou s situation s ar e avoide dandasaf

e autorotativ e landing ca n b e execute din th e even

t o f engine failure
. Following a

n engin e failur

e i n ahelicopter , it s roto r

mus t transitio n frompropulsiv e state t o autorotativ e state , an dth e ensuin g landin g i s alway s a n emergenc y procedure
. The pilo t mus t manually establis h an

d maintain rotor

RP M wit h collectiv e pitc h contro l whil e simultaneously establishin g an dmaintainin g th e requiredglid e airspee d(which als o govern s roto r RPM ) wit h th e cycU c pitc h control
. Helicopter s ma y execut e a n autorotativ e emergenc y landin g wit h eithe r acollectiv e flare or

acycli c flare. Landin g froma collectiv e flare i s th e les s commo n o f th e tw o type s o f

emergenc y landing s sinc e thes e require a favourable combinatio n o f

wind , densit

y altitude , hig h roto r

inertia , roto r

RPM , aircraf

t gros s weight , an

d pilo t techniqu e fo

r th e successful outcom

e o f th e procedure
. Mos t

emergenc y landing s froma n autorotativ e descen

t are execute dwit

h acycU c flare sinc e th e aforementione dfavourabl e condition s ar e no t alway s reliabl y present . A cycli c flare inevitably result s in arun-on landing durin g whic h th e helicopte r — particularl y thos e wit

h ski dlanding gea

r —i s highly pron e t o rollover
. I n either case , thes e landing s ar

e a n emergenc y conditio n fo

r which ahelicopter

i s designe dto provid e adequate , thou ^ fa r fromoptimal , performance
. A gyroplane i s equally capabl e o f saf e operatio n a

t lo w altitudes , but

sinc e it s roto r

i s alway s in autorotation , landin g afte

r engine failur

e i s anorma

l procedure
. The mai

n concemfo

r th e pilo t i s t o establis h andmaintai n th e require dglid e airspeed ; managemen t o f roto r RP M i s no t aconsideration
. Touchdow n ma y b e followedby alanding run , but i s usually o f

minimal , if

any , length , again dependin g

### Jean-Pierr

e Harriso n Pag e 3 o f 5 1183 5 Skyline Blvd
. Lo s Gatos,C A 9503 3 US A 408/872-125 7 6 July 201 1 on airspee da

t touchdown , weight , densit y altitude , wind , andpilo t

technique
. Gyroplane s ma

y b e fittedwit

h collectiv e pilc h contro l (Avia n 2-180 ) or

acollectiv e pitc h tri m(Ai

r & Spac e 18A)
. I

n th e cas e o f

th e former, acollectiv e flare t o alanding froma n autorotativ e descen

t i s a norma l procedur e fo r whic h th e gyroplane i s designed
. Th e collectiv e pitc h trimfitted t o th e Air & Spac e 18 A doe s no t

ac t quickly enough t o enabl e alandin g fro macollectiv e flare. Gyroplane s in genera l ar e landedfrom acycli c flare, whic h due to th e low roto r dis k loading necessar

y t o provid e adequat

e performance , i s followedb y minima l —i f an y — groundrol l usually n o longe r tha n th e lengt h o f th e aircraft
. Experienc e show s conclusively tha t acurren t FA A certificate dgyroplan e pilo t flying a n FA A Standar dAirworthines s Categor

y gyroplan e —

th e intende dbeneficiar

y o f thi s petitio n —ca

n execut e a no-roll landin g from acycli c flare a s anorma l procedure
. For

example , a

n Ai r & Spac e 18A ca

n easily operat e to andfrom ahelipad—andha s don e s o man y time s a s amatte

r o f norma l procedure
. An

y groun droll afte r touchdow n i s als o anoima l procedur e sinc e agyroplan e i s designe dt o operat e a t speed on it s landing gea

r when executin g arollin g takeoff
. I t i s seen tha

t following a

n engin e failure , agyroplan e operate s normally wit h th e adde dadvantag e o f requiring les s are afo

r asafe , minimu

mgroundroll landin g tha

n a n comparabl e helicopter

whic h mus t

b e establishe din stabl e autorotatio n befor e touchin g down andusually requiring agroundru n t o complet

e th e landing procedure
. I n summary , th e gyroplan e offer s equa l or bette r level s o f safet y following a

n engin e failur

e tha n doe s a comparabl e helicopter
. Supportin g Informatio n Height-Velocit

y Limitation s I n bot h gyroplane s andhelicopters , th e pilo t mus t avoi dviolatin g th e height-velocit y limitation s specifie d in th e Approve dFligh

t Manual
. Height-velocit

y limitation s ar

e les s restrictiv e fo

r gyroplane s compare dto helicopter s a s ca

n b e seen fromth e example s include din Height-Velocit y Graph appendices
. Gyroplane height-velocit

y chart s hav e one avoi dregion ; heUcopte r heigh t velocit y chart s hav e tw o avoi d regions. The high altitude/lo w airspee davoi dregio n i s common t o bot h gyroplan e andhelicopter
. It s purpos e i s to infor

mth e pilo t

o f th e combinatio n o f

altitude/airspee dfro

mwhic h it

i s no t possibl e to land th e aircraf t without hazar dfollowm g engin e failure
. I

n th e gyroplan e case , th e main hazar di s ahar d landing due t o excessiv e descen t rate an dinsufficien

t airspee dt o trade fo

r increase droto r

thrus t in a cycli c flare; in th e helicopter case , th e hazar

di s complet

e los s o f contro l on landin g du e t o inabilit y to establis h stabl e autorotatio n an dstabiliz e th e descen t rate. I n th e cas e wher

e ahelicopter

i s establishe din astabl e autorotativ e descent , flight throug h th e avoi dregio n o f th e height-velocit

y char t wil l als o result

in damag e to th e aircraf

t on landin g fo

r th e sam e reasons affecting agyroplane
. A helicopter i n a n autorotativ e descen

t i s nothin g mor

e tha n a n gyroplan e rendere dinefiicien t becaus e o f

hig h dis k loading , negativ e rotor

blad e twist , andpowe

r losse s arisin g fromth e tai l roto r driv e system .

### Jean-Pierr

e Harriso n Pag e 4 o f 5 1183 5 Skyline Blvd
. Lo s Gatos,C A 9503 3 US A 408/872-125 7 6 July 201 1 Th e lowe r altitude/hig h airspee davoi dregion applie s only t o helicopters
. Engine failur e a t lo w altitude/high airspee dprovide s th e pilo t insufficien

t tim e t o establis h stabl e autorotatio n befor e th e helicopte r contact s th e ground
. I

n addition , th e high aircraf

t pitc h angl e required t o decelerat e th e helicopte r fo r landin g easil y result s in th e tai l rotor strikin g tiie ground
. Eithe

r o f thes e factor s easil y results in los s o f

contro l o f th e helicopte

r durin g touchdown
. A t 10 0 fee t AGL , Air & Spac e 18

A mus t maintai n aminimu

mairspee do f

3 6 mph , an dth e Enstro mF-2 8 aminimu mairspee do f

3 0 mph t o remain outside thei r respective height-velocit

y graph avoi dregions. A

t 30 0 fee t AGL , bot h Air & Spac e 18

A an dEnstro mF-2 8 bot

h hav e aminimumairspee do f 0 mp h to remain outsid e theu " respective avoi dregions. I n contras t t o th e Enstro mF-28 , th e Air & Spac e 18

A ca n operat e safely , indefinitely , a

t altitude s belo w 5 0 ft

a t aminimumairspee do f

4 5 mph
. Descen t Rate s Durin g Engine-Ou t Autorotatio n Sinc e agyroplan e rotor

i s designe dt o fly a

t all time s in autorotativ e state , it i s generall y designe dt o b e a s efficien t a s possibl e i n thi s flight

condition
. Conversely , ahelicopte r rotor i s designe dt o fly i n propulsiv e stat e unde r norma l conditions , wit

h autorotativ e state bein g th e emergenc y case . I t follow s tha

t a helicopte r rotor i s designe dprimarily fo

r efficiency durin g propulsiv e state , wit h only minimum efficienc y a s necessar

y bein g provide dfo

r operatio n i n autorotativ e state . Th e endresul t i s tha t afte r a n engine failure , th e gyroplan e roto r i s operatin g under

norma l conditions , andth e helicopter roto r i s operatin g under

emergenc y conditions
. The resulting descen t rate fo r agyroplan e i s approximately one thir dtha t o f acomparabl e helicopte

r a s ca n b e seen below
. Th e followm g tabl e present s alis t

o f gyroplane s tha

t hav e receive dApprove dType Certificate s fromth e FA A or it s predecessor , th e CAA
. A s ca n b e seen , th e Pitcai mPA-2 4 ha dlowes t dis k loadin g o f 1.3 9 Ib/ft ^ andtiie McCulloch J- 2 th e highes t dis k loadin g a t 3.0 0 Ib/ft ^ It mus t b e note dtiiat

tiie McCulloch J

2 dis k loading valu e i s anomalou s i n tha t it i s th e sol e exampl e exceedin g th e next highes t dis k loadin g valu e o f 2.0 5 lb/ft= * fo r tiie Pitcai mPA-19 , andtha t b y a50 % margin
. In general , adis k loadin g o f

2.00 Ib/ft ^ ha s bee n establishe da s a

n uppe r limit fo r goo dperformanc e in gyroplanes ; performanc e o f th e McCulloch J- 2 wa s ver

y poo r a s ca n b e readily verifie dfromit s Approve dFlight Manual
. Nevertheless , a pilo t ca n routinel y execut

e ano-roll landin g in th e McCulloch J-2
. Th e averag e dis k

loadin g fo

r all gyroplane s liste dbelo w i s 1.89 Ib/ft^
. Th e averag e dis k

loadin g fo

r al l gyroplane s liste dbelo w excep t th e McCulloch J- 2 i s 1.8

0 Ib/ft^
.

### Jean-Pierr

e Harriso n 1183 5 Skylm

e Blvd
. Lo s Gatos , C

A 9503 3 US A 408/872-125 7 Gyroplan e Make/Mode l Pitcaim-Cierv aPCA- 2 Pitcaim-Cierv aPCA- 3 PitcaimPAA-l/PA-2 0 Pitcai mPA-1 8 PitcauT i PA-1 9 PitcaimPA-2

4 Kellet t K- 2 KellettIC- 3 Kellet t KD- 1 Kellet t KD-I A Kellet t KD-I B Ai r & Spac e 18

A McCulloch J- 2 Avia n 2-18 0 Pag e 5 of 5

6 July 201 1 ATC/FA A Typ e Certiiicat e Numbe r 41 0 44 6 43 3 47 8 50 9 50 7 43 7 47 1 71 2 71 2 71 2 1H1 7 H6W E H5E A Dis k 1.8 9 1.9 3 1.6 5 1.5 1 2.0 5 1.3 9 1.7 2 1.8 2 1.7 9 1.9 1 1.9 1 1.8 7 3.0 0 1.9 9 

### Dis k Loadin g lb/ft '

Autorotativ e performanc e o f arotorcraft

i s dependen

t primaril y on dis k

loading andblad e inertia
. The averag e dis k

loadin g for

helicopter s i s 5~1 0 Ib/ft

^ which result s in descen

t rates a t bes t glid e airspee d ranging fromapproximately 1,800-3,60 0 FP M (Leishman , p.43,62)
. For th e gyroplan e dis k

loading s o f 1.39-3.0 0 Ib/ft^ , th e correspondin g descen t rates ar e approximately 500-1,10 0 FPM
. Fo r th e averag e gyroplane dis k

loadin g o f

1.8 9 Ib/ft^, th e correspondin g descen t rate i s approximately 70 0 FPM
. Appendice s 1
. Ai r & Spac e 18A gyroplan e height-velocit y graph
. 2
. McCulloch J- 2 gyroplan e height-velocit y graph
. 3
. EnstromF-2 8 helicopter height-velocit

y graph
. 4
. Robinson R-2 2 helicopte r height-velocit

y graph
. 5
. Petitio n Docket

FAA-2009-0838
. 6
. FA A denia l letter to petitio n Docke

t FAA-2009-0838
. 7
. Petitione

r respons e t o FA

A denia l letter to petitio n Docke

t FAA-2009-0838
. Reference s Leishman , J
. Gordon
. Principle s o f Helicopte r

Aerodynamics , Ne

w York
. Cambridg e Universit y Press , 2000
.

Jean-Pierr e Harriso n

### EHEIGH T VS
. vSLOCltY : •=rl":^g^F =



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## Robinso n R-2 2 Height-Velocit y Grap hJean-Pierr e Harriso n Pag e I o f 8 410 7 Elderwoo d Seabrook , T

X 7758 6 281/326-118 8 jp( aselec.ne t Petitio n t o Appl y FA R§91.119(d ) Minimu mSaf e Altitudes : General : Helicopter s t o al l Rotorcraf t Explanatio n o f

Propose dActio n an dIt s Purpos e There hav e historicall y been thre e fundamenta l type s o f rotorcraft , gyrodyne , gyroplane , andhelicopter , o f whic h th e latte r tw o have been continuall y i n servic e sinc e thei r

inception
. Certificatio n andoperationa l regulation s fo r helicopter s hav e been develope dan drefine dsinc e it s emergenc e a s apractical aircraf t andcurrentl y reflect

th e capabilitie s an dlimitation s o f thi s clas s o f aircraft
. Th e same i s not

tru e fo r th e gyroplane s th e op>eratio n o f whic h ar e sometime s governe db y helicopte r regulation s andsometime s b y Mrplane regulations. Gyroplane s hav e b

y an dlarg e bee

n historicall y regardeda s testbed s fo r rotary-wing development
. Successiv e model s o f gyroplane s manufacture db y Licensee s o f

th e Cierv aAutogiro Company , Ltd
. (Autogiro Company o f America , etc. ) eac h furthere dth e developmen t o f th e rotary wing , wit

h th e resul t

tha t th e technolog y neve

r mature dunti l abou t

th e mi d1930s
. Thi s rotary-win g technolog y wa s use di n th e first successfu l helicopter s such a s th e Sikorsk y VS-300 , Sikorsk

y R-4 , Bel l 47 , Kama n K-225 , etc . Helicopte r

developmen t

thereafter displace dfurther

gyroplan e effort s wit

h th e exceptio n o f

thre e FA A certificate dexample s o f

th e latter (Ai r & Spac e 18A , Avia

n 2-180 , McCulloc h J-2 ) t o th e curren t time
. Thi s lack

o f attentio n ha s resultedi

n th e Federal Aviatio n Regulation s becomin g ou t o f dat e wit h regardt o gyroplan e capabilities
. Thepurposeo f

thi s petitio n i s t o appl y FA R§91.119(d

) MinimumSaf

e Altitudes : Genera l \aa\ \aircraf t classe s withi n th e rotorcraft category , i.e
. gyrodyne , gyroplane , andhelicopter , fo r th e followin g reasons . 1 Appl y consisten t

regulation s t o al l aircraf

t classe s withi n th e rotorcraft categor y whe n thos e aircraf

t posses s commo n capabilities
. 2 Remov e limitation s fro mgyroplan e operation s whic h restric t th e usefulnes s o f

thi s clas s o

f aircraf t withou t providin g an

y increas e i n safety
. 3 Recognitio n o f

th e resurgence o f

interes t i n anddevelopmen t

o f gyroplanes
. A

t th e time o f

writing , ther e ar e tw o well

funded , professionall y manage dgyroplan e developmen t effort s (CarterCopters , www.cartercopters.co man dGroen Brother s Aircraft , www.groenbros.co mi n additio n t o thos e develope dunder th e Light Spor t Aircraf t Categor y (LSA ) certificatio n regulations.

Propose dLanguag e fo r

Redeflnitio n o f

FA R§91.119(d ) Minimu mSaf e Altitudes : Genera l d) Rotorcraft
. Rotorcraf

t ma y b e operate da

t les s tha n th e minimum s prescribe di n paragrap h (b ) o r (c ) o f thi s sectio n i f

th e operatio n i s conducte dwithou t hazardt o person s o r propert y o n th e surface
. I

n addition , eac h perso n operatin g arotorcraf t shal l comply wit

h an y route s o r

altitude s specificall y prescribe dfo r rotorcraf t b y th e Administrator
. Th e ter mrotorcraf

t replaces th e origina l termhelicopte r i n th e preceding
. Publi c Interes t

Serve db y th e Propose dActio n Th e publi c interes t

serve db y th e propose dactio n i s consisten t regulatio n o

f al l aircraf t classe s withi n th e rotorcraf t categor y b y eliminatin g unnecessar

y altitud e hmitation s whil e maintainin g safet y a t leas t a t curren t levels
. Thepurposeo f

th e existin g regulation, FA R§91.119(d

) Minimu mSaf e Altitudes : General , i s t o permi t helicopte r

operadon s a t an y altitud e providin g hazardou s situation s ar e avoide dandasaf

e autorotativ e landin g can b e execute di n th e event o fJean-Pierr e Harriso n Pag e 2 o f 8 410 7 Elderwoo d Seabrook , T

X 7758 6 281/326-118 8 iD@selec.ne

t engin e failure
. Followin g a

n engin e failur

e i n ahelicopter , it s roto r

mus t transitio n fro

mpropulsiv e stat e t

o autorotativ e state , an dth e ensuin g landin g i s alway s a

n emergenc y procedure ; th e pilo t mus t manuall y estabUs h an dmaintai n rotor RPM whil e simultaneousl y estabUshin g an dmaintainin g th e require dglid e airspeed
. Landin g i s usually followedb y arun , th e lengt

h o f whic h varie s wit h airspee da

t touchdown , weight , densit y altitud e andwin d A gyroplan e i s equall y capabl e o f saf e operatio n a

t lo w aldtudes , bu t

sinc e it s rotor

i s alway s i

n autorotation , landin g afte r engin e failur

e i s essentiall y anorma

l procedure ; th e mai n conce mfo r th e pilo t i s t o establis h andmaintai n th e requiredgUd e airspeed ; maintenanc e o f

rotor RP M i s no t aconsideration
. Touchdow n ma y b e followed b

y alandin g run , but

i s usuall y o f minimal , i f

any , length , agai n dependin g o n airspee da t touchdown , weight , densit y altitud e andwind
. I t i s seen tha

t followin g a

n engin e failure , agyroplan e operate s normall y wit h th e adde dadvantag e o f

requirin g les s are afo

r a safe , minimu mgroun droll landin g tha n a n comparabl e heUcopte

r whic h mus t

b e establishe di

n stabl e autorotatio n befor e touchin g dow n an dusuall y requirin g agroun dru n t o complet e th e landin g procedure
. I n summary , th e gyroplan e offer s equa l o r bette r level s o f safet y followin g a

n engin e failur

e tha n doe s acomparabl e helicopter
. Supportin g Informatio n Height-Velocity Limitation s I n bot h gyroplane s andhelicopters , th e pilo t mus t avoi dviolatin g th e height-velocit y limitation s specifie di

n th e Approve d Flight Manual
. Height-velocit

y limitation s ar

e les s restrictive fo

r gyroplane s compare dt o helicopter s a s ca n b e see n fro

mth e example s include di

n Appendi x I : Height-Velocit y Graphs
. Gyroplan e height-velocit

y chart s hav e on e restricte dheight-velocit y region; helicopte r

heigh t velocit y chart s hav e tw o restricte dheight-velocit

y regions. Th e highe r

altitude/lo w airspee drestrictedheight-velocit y region i s commo n t o bot h gyroplan e an dhelicopter
. It s purpos e i s t o infor mth e pilo t

o f th e combinatio n o f

altitude/airspee dfro

mwhic h i

t i s no t possibl e t o landth e aircraf t withou t hazar dfollowin g engin e failure
. I n th e gyroplan e case , th e mai n hazardi s ahar dlandin g du e t o excessiv e descen t

rate i n th e helicopte r

case , th e hazardi s complet e los s o f contro l o n landin g du e t o inabilit

y t o establis h stabl e autorotatio n an dstabiliz e th e descen t rate . Th e lowe r altitude/hig h airspee drestrictedheight-velocit y region applie s only t o helicopters
. Engin e failur e a t lo w altitude/hig h airspee dprovide s th e pilo t wit h insufficient

tim e t o establis h stabl e autorotatio n befor e th e helicopte r

contact s th e ground
. I

n addition , th e hig h pitc h angl e require dt o decelerat e th e helicopte r fo r landin g easil y results i

n th e tai l rotor strikin g th e ground
. Eithe r o f thes e factor s easily result s i n los s o f contro l o f th e helicopter

durin g touchdown
. A t 10 0 fee t AGL , Ai r

& Spac e 18

A mus t maintai n aminimu mairspee do f 3 6 mph , andth e Enstro mF-2 8 aminimu mairspee d o f 3 0 mph t o remain outsid e thei r respective restrictedheight-velocit y regions. A

t 30 0 fee t AGL , bot h Ai r & Spac e IS A and Enstro mF-2 8 bot

h hav e aminimu mairspee do f 0 mph t o remain outsid e thei r respective restricte dheight-velocit y regions. I

n contras t t o th e Enstro mF-28 , th e Air & Spac e IS A ca

n operat e safely , indefinitely , a t altitude s belo w 5 0 ft

a t aminimu m airspee do f

4 5 mph
.Jean-Pierr e Harriso n Pag e 3 o f 8 410 7 Elderwoo d Seabrook
. T

X 7758 6 281/326-118 8 jpt a<ialec.ne

t Descen t Rate s Durin g Engine-Ou t Autorotatio n Sinc e agyroplan e rotor

i s designe dt

o fl y a t al l time s i

n autorotativ e state , i t

i s generall y designe dt o b e a s efficient a s possibl e i n thi s flight

condition
. Conversely , ahelicopte r rotor i s designe dt o fl

y i n propulsiv e state under

normal conditions , wit h autorotativ e state bein g th e emergenc y case . I t follow s tha

t ahelicopte r

rotor i s designe dprimaril y fo

r efficienc y durin g propulsiv e state , wit

h only minimu mefficienc y a s necessar y bein g provide dfo

r operatio n i

n autorotativ e state . Th e en dresul t i s tha t afte r a n engin e failure , th e gyroplan e roto r i s operatin g under

norma l conditions , andth e helicopte r rotor i s operatin g unde r emergenc y conditions
. Th e resulting descen t rat e fo r agyroplan e i s approximatel y one-thir dthat o f acomparabl e helicopte r a s ca n b e see n below
. Th e followin g tabl e present s ahs t o f gyroplane s tha

t hav e receive dApprove dTyp e Certificate s fro mth e FA A o r it s predecessor , th e CAA
. A s can b e seen , th e Pitcai mPA-24 hadlowes t dis k loadin g o f

1.3 9 Ib/ft ^ an dth e McCulloc h J- 2 th e highes t dis k loadin g a t 3.0 0 Ib/ft^
. I

t mus t b e note dtha

t th e McCulloc h J- 2 dis k

loadin g valu e i s anomalou s i n tha t i t i s th e sol e exampl e exceedin g th e nex t highes t dis k loadin g valu e o f

2.0 5 Ib/ft ^ fo r th e Pitcai mPA-19 , an dthat b y a50 % margin
. I

n general , adis k

loadin g o f

2.0 0 Ib/ft ^ ha s bee n establishe da s a n upper limi t fo r goo dperformanc e i

n gyroplanes ; performanc e o f th e McCulloc h J- 2 wa s ver y poo r a s ca n readil y b e verifie dfro

mit s Approve dFligh t

Manual
. Th e averag e dis k

loadin g fo

r al l gyroplane s liste dbelo w i s 1.8 9 Ib/ft^
. Th e averag e dis k

loadin g fo

r al l gyroplane s liste dbelo w excep t th e McCulloc h J- 2 i s 1.8

0 Ib/ft^
. Gyroplan e Make/Mode l Pitcaim-Cierv aPCA- 2 Pitcaim-Cierv aPCA- 3 Pitcai mPAA-l/PA-2 0 Pitcai mPA-1 8 Pitcai mPA-1 9 Pitcai mPA-2

4 Kellet t K- 2 Kellet t K- 3 Kellet t KD- 1 Kellet t KD- 1 A Kellet t KD-I B Air & Spac e IS A McCulloc h J- 2 Avia n 2-18 0 ATC/FA A Typ e Certificat e Numbe r 41 0 44 6 43 3 47 8 50 9 50 7 43 7 47 1 71 2 71 2 71 2 1H1 7 H6W E H5E A Dis k Loadin g Ib/ft ^ 1.8 9 1.9 3 1.6 5 1.5 1 2.0 5 1.3 9 1.7 2 1.8 2 1.7 9 1.9 1 1.9 1 1.8 7 3.0 0 1.9 9 Autorotativ e performanc e o f arotorcraft

i s dependen t

primaril y o n dis k

loadin g andblad e inertia
. Th e averag e dis k loadin g fo r helicopter s i s 5-1 0 lb/ft ' whic h result s i n descen t rate s a t bes t glid e airspee drangin g fro mapproximatel y 1,800-3,60 0 FP M (Leishman , p.43,62)
. Fo r th e gyroplan e dis k

loading s o f

1.39-3.0 0 Ib/ft^ , th e correspondin g descen t rate s ar e approximatel y 500-1,10 0 FPM
. For th e averag e gyroplan e dis k loadin g o f

1.8 9 Ib/ft^ , th e correspondin g descen t rat e i s approximatel y 70 0 FPM
.Jean-Pierr e Harriso n Pag e 4 o f 8 410 7 Elderwoo d Seabrook , T

X 7758 6 281/326-118 8 jp@selec.ne t Appendi x 1 : Height-Velocity Graph s 1
. Air & Spac e 18

A gyroplan e 2
. McCulloc h J- 2 gyroplan e 3
. Enstro mF-2 8 helicopte r 4
. Robinso n R-2 2 helicopte r

# Q

U.S
. Departmen t 80 0 Independence Ave. , S.W
. o f Transportatio n Washington , D C 2059 1 Federa l Aviatio n Administratio n De c 1 5 201 0

Mr
. Jean-Pierr e Harriso n 1183 5 Skylin e Boulevar d Lo s Gatos , C A 9503 3 Dear Mr
. Harrison : I n you r Augus t 29 , 200 9 letter , yo u petitione dth e Federa l Aviatio n Administratio n (FAA ) t o amen d§ 91.119(d ) o f Titl e 14 , Cod e o f

Federa l Regulation s (1 4 CFR ) b y changin g "helicopter " t o "rotorcraft. " Thi s chang e woul dthe n includ e gyroplanes
. Yo u hav e mad e som e goo dpoints
. However , whe n th e FA A respond s t o petition s for rulemaking , i t

mus t follo w th e requirement s o f 1 4 CF Rpar t

11 , particularl y thos e guideline s fo r

processin g petition s fo r

rulemakin g foun di n § 11.73
. A s state di n tha t section , th e FA A use s th e followin g criteri awhe n makin g adecisio n a s t o whethe r o r no t t o amen dcurren t

regulation s basedo n apetitio n fo r rulemaking : 1 ) th e immediac y o f

th e safety o r

securit y concern s th e petitio n raises ; 2 ) th e priorit y o f

othe r FA A issues ; an d 3 ) th e resource s w e hav e availabl e t o addres s thes e issues
. Mos t gyroplane s flow n i n th e Unite dState s ar e registere da s "Experimental-Amateu r Built " o r a s Ligh t Spor t Aircraf t (LSA)
. Onl y afe w ar e FA A certificated
. Sinc e §91.31 9 doe s no t

allo w experimenta l aircraf t t o b e operate dove r

adensel y populate d are ao r i n acongeste dairway , the y woul dno t b e allowe dt o operat e ove r acongeste dare a a t an y altitud e o r

exercis e th e privilege s o f § 91.119(b ) o r

us e helicopte r

route s whic h ar e normall y considere dt o b e heavil y congeste dairways
. Helicopter s operat e a

t lowe r altitude s i n congeste darea s t o perfor maeria l work suc h as : new s gathering , securit y surveillance , construction , an dtransportatio n fro mon e locatio n t o anothe r

withi n acongeste dare awithou t requirin g awaive r

fo r eac h operation
. Thi s i s no t applicabl e t o mos t

gyroplane s sinc e experimenta l aircraf t may no t b e use dfo r commercia l purposes , an dgyroplane s ar e no t abl e t o hover , whic h i s anecessar y par t o f a larg e portio n o f

aeria l work

fo r helicopters
. AFS-09-393- PNormally , helicopte r pilot s ar e require dt o hav e mor e trainin g an dahighe r certificatio n leve l tha n gyroplan e pilot s sinc e man y gyroplane s ar e operate db y LS A pilot s whil e helicopte r

pilot s mus t

hav e a t leas t aprivat e pilo t

certificate
. Acceptin g th e propose d chang e i n thi s rul e woul dhav e a n advers e affec t o n safet y b y allowin g les s skillfu l pilot s t o fly lowe r

an dclose r

t o congeste dareas . Th e FA A continue s t o commi t resource s t o develo p helicopte r route s ove r

an dthroug h congeste darea s t o channe l helicopte r traffi c alon g flight

path s t o avoi dth e flow o f airplanes
. Safet

y o f thes e route s coul db e compromise di f th e FA A allowe dmuc h les s capabl e gyroplane s t o fly o n thes e routes . Th e FA A finds tha t

th e height-velocit y (HA^ ) curv e yo u reference donl y applie s t o tak e off s an dleve l flight

wit h power . I t

i s no t appropriat e t o conside r

th e H/ V curv e i n a n autorotativ e landin g a s aresul t o f apowerplan t

failur e whic h i s th e focu s o f § 91.119
. Helicopter s hav e th e abilit y t o vary thei r glid e pat h durin g a n autorotativ e landin g t o a greate r degre e usin g collectiv e pitc h applications , whic h ca n b e use dt o complet e a n autorotativ e landin g wit h very littl e o r n o groun drun . Fe w gyroplane s ar e equippe dwit h controllabl e collectiv e pitc h t o us e fo r autorotativ e landin g wher e thes e collectiv e pitc h application s ma y b e used
. Sinc e gyroplane s var y i n desig n capabilities , i t woul dno t

b e pruden t fo r th e FA A t o allo w al l gyroplane s t o exercis e th e sam e privilege s fo r whic h ver y fe w gyroplane s qualify
. Fo r th e reason s above , w e ar e tinabl e t o conside r an dthereb y den y you r

petitio n fo r rulemakin g i n accordanc e wit h 1 4 CF R§ 11.73
. Accordingly , Docke t

No
. FAA-2009-083 8 i s bein g closed
. Sincerely ,
RaymcUi d Towle s Actin g Director , Fligh t Standard s Servic eJean-Pierr e Harriso n 1183 5 Skylin e Blvd
. Lo s Gato s C A 9503 3 US A 408/872-125 7 jph@wt.ne t 6 Jul y 201 1 Actin g Director , Fligh t

Standard s Servic e Federa l Aviatio n Administratio n 80 0 Independenc e Avenue , S W Washington , D C 2059 1 Dea r Sir , Than k yo u fo r you r lette r of 1 5 Decembe r

201 0 (cop y enclosed)
. Sinc e it s receip t I hav e debate d whethe r i t i s worthwhil e t o respon dt o th e statement s containe dtherei n sinc e the y base do n aselectiv e interpretatio n o f

th e relevan t

Federa l Aviatio n Regulations , includ e unsupportabl e assertions , an d disclos e afundamenta l lac k o f understandin g o f

rotary-win g aircraf

t operations
. Thes e statement s ar e even mor e disheartenin g sinc e the y originat e fro mth e headquarter s o f th e agenc y responsibl e fo r promotin g an dregulatin g aviatio n operation s i n th e Unite dStates , an don e woul dexpec t arespons e t o an y petitio n t o b e a t

leas t consistent , logical , accurate , an dobjective
. Pleas e not e tha t

comment s i

n thi s fon t

originat e fro mMr
. Jo n Stark , a n intereste dpart y t o thi s petition , wh o lik e mysel f

hold s CPL/an dCF I gyroplan e pilo t certificate s amon g othe r qualifications , an dwh o als o regularl y operate s tw o gyroplane s certificate di n th e Standar dCategor y b y th e FAA
. Mr
. Star k i s als o a n attorney . M y petitio n (cop y enclosed ) wa s restricte dt o changin g FAR91.119(d) b y replacin g helicopte r

with rotorcraft , thu s extendin g th e waive r o f minimu maltitud e requirement s t o gyroplane s an dgyrodynes
. To quot e therefrom : Propose dLanguag e for

Redefinitio n o f

FAR91.119(d ) Minimu mSaf e Altitudes : Genera l d) Rotorcraft
. Rotorcraf t ma y b e operate da

t les s than th e minimum s prescribe di n paragrap h (b ) o r (c ) o f this sectio n if

th e operatio n i s conducte dwithou t hazar dt o person s o r

propert y o n th e surface
. I n addition , eac h perso n operatin g arotorcraf t shal l compl y with an

y route s o r

altitude s specificall y prescribe dfo r rotorcraf t b y th e Administrator
. I n lighto f th e change s t o FAR91.11 9 arisin g fro mth e adven t o f ligh t sport aircraf t (LSA ) an dspor t pilo t certification , sai dregulation , effectiv e a s o f 2 Apri l 201 0 follows :FAR91.119 : Minimu mSaf e Altitudes : General
. Excep t whe n necessar y for

takeof f o r landing , n o perso n ma

y operat e a

n aircraf t belo w th e followin g altitudes : a) Anywhere
. A n altitud e allowing , i f apowe r uni t fails , a n emergenc y landin g withou t undu e hazar dt o person s o r properl y o n th e surface
. b ) Ove r

congeste dareas . Ove r

an y congeste dare ao f

acity , town , o r

settlement , o r

ove r an y ope n ai r assembl y o f

persons , a

n altitud e o f

1,000 fee t

abov e th e highes t

obstacl e withi n a horizonta l radiu s o f

2,00 0 feet

o f th e aircraft
. c ) Ove r

othe r tha n congeste dareas . A n altitud e o f 50 0 feet abov e th e surface , excep t over ope n wate r

o r sparsel y populate dareas . I n thos e cases , th e aircraf t ma y no t b e operate dclose r than 50 0 feet

t o an y person , vessel , vehicle , o r structure . d) Helicopters , powere dparachutes , an d weight-shift-contro l aircraft
. I f th e operatio n i s conducte dwithou t

hazar dt o person s o r

propert y o n th e surface

1 ) A helicopte r

ma y b e operate da

t les s than th e minimum s prescribe di n paragrap h (b ) o r (c ) o f thi s section , provide deac h perso n operatin g th e helicopte r complie s wit

h an y route s o r altitude s specificall y prescribe dfo r helicopter s b y th e FAA ; an d 2 ) A powere dparachut e o r weight-shif

t contro l aircraf

t ma y b e operate da t

les s tha n th e minimum s specifie di n paragrap h (c ) o f this section
. 1 ) You r respons e immediatel y referre dt o experimenta l gyroplane s whic h du e t o restriction s o f thei r airworthines s certificatio n categor y ar e prohibite dfro moperation s over congeste darea s o r

alon g a congeste dairway (FAR91.319(c))
. Thes e restriction s appl y t o al l experimenta l aircraf t i n an y category/class , no t

jus t gyroplanes
. M y petitio n di d no t reques t waive r o f fligh t operatin g limitation s fo

r experimenta l rotorcraf

t a s governe db

y FAR91.319
. You

r respons e conflate dth e operatin g limitation s o f tw o differen t

aircraf t certificatio n categories
. I f experimenta l aircraft ar e alread y prohibite d fro m flyin g ove rcongeste d area s an d airways , the n grantin g th e petitio n coul d no t possibl y reduc e th e safet y o f operatio n of experimenta l aircraf t ove rthos e regions , sinc e ther e wil l not b e an y suc h operations
. Yo u contradic t yourself
. Wit h respec t t o you r statemen t

regardin g th e variou s use s o f helicopter s i n lo w altitud e operations , i t i s amatte r o f recor dtha t

gyroplane s hav e bee n an d ar e safely an d successfull y use di n new s gathering , security surveillance , construction , an d transportatio n fro mon e locatio n t o anothe r withi n congeste d areas . Th e ability o

f helicopter

s t o hove rha s n o relevanc e t o a questio n of saf e altitude s fo r operations
. Th e necessit y o f hoverin g i s bot h overstate d an d no t germane . Gyroplane s ma y als o b e use d fo rnew

s gathering , security surveillance , an d transportation , withou t hovering , as wel l as aeha l photography , mapping , an d othe rtasks , an d lik e helicopters , ma

y b e operate d a

t airspeed s dow n t o zero withou t ris k of lo w altitud e stall/spi n incidents
. N o aircraf t hover s i n a n emergenc

y landing
.You

r statemen t

that helicopte r

pilot s ar e require dt o hav e mor e trainin g an d highe r certificatio n leve l than gyroplan e pilot s i s are d herrin g sinc e yo u follo w this b y arguin g tha t th e petitio n woul dallo w lesse r traine dgyroplan e pilot s (presumabl y sport pilot s flyin g experimenta l gyroplanes , LS A gyroplanes , o r

certificate dgyroplane s tha t mee t LS A rules ) t o fl y lower

i n congeste dareas . Thi s statemen t ignore s FAR91.119(d)(2 ) whic h explicitl y permit s powere dparachute s o r weight-shif

t contro l aircraft , whic h ar e invariabl y certificate di n th e experimenta l o r LS A categorie s operate db y spor t pilots , an d whic h wa s effectiv e eigh t months a s o f

th e dat e o f

you r lette r o f 1 5 Decembe r

2010
. You

r statemen t i s essentiall y tha t

helicopte r

pilot s holdin g an y FAA pilo t certificat e o f

PP L an d abov e ar e safer tha n an y pilo t

holdin g a

n FAA spor t

pilo t certificate , bu t

aselec t grou p o f th e latte r ar e exemp t fromth e minimu maltitud e rules
. You r statemen t

als o ignore s th e fac t

tha t a n aircraf t supporte di n fligh t b y a n autorotatin g roto r

maintain s ful l contro l a t an y airspee dan d i s a

t leas t a s safe,i f no t safer , than apowere dparachut e o r weight-shif

t contro l aircraf

t a t an y altitude
. Th e additiona l trainin g require d o f helicopte rpilot s ove rgyroplan e pilots , t o th e exten t i t exist s a t all , reflect s onl y master y o f thos e task

s require d fo rprivat e pilot s o f gyroplane s tha t ar

e no t require d fo rspor

t pilot s o f gyroplanes
. Accordin g t o Par t 61 , tha t trainin g consist s of nigh t fligh t an d towere d airpor t operations , neithe ro

f whic h hav

e an y bearin g o n minimu m saf e altitude s fo roperation
. I t i s th e state d positio n o f th e FA A tha t spor

t pilot s ar

e teste d t o a standar d tha t ensure s th e safet y o f th e public
. I f thi s i s no t th e case , a s suggeste d b y you r characterizatio n of spor t pilot s as les s skillful , the n th e issu e i s Impruden t rulemakin g wit h respec t t o spor t pilo t standard s and/o rlac k o f oversight/enforcemen t of suc h testin g standard s b y th e FAA
. I t i s incumben t upo n th e FA A t o correc

t an y suc h deficiencie s at once , a s a matte ro f safet y fo rall
. I t doe s not provid e a basi s fo rdenyin g th e petition
. You r statemen t

tha t th e safely o f

helicopte r

route s coul db e compromise dif th e FA A allowe dallowe d muc h les s capabl e gyroplane s t o fly o n thes e route s i s a t bes t a n unsupportabl e assertion
. A helicopte r rout e i s essentiall y n o differen t than aVF Rflywa

y throug h Clas s B airspace
. VF Rflyway s ar e no t restricte dt o aircraf

t o f minimu mperformanc e capabilitie s bu t ar e nevertheles s safel y use db y hundred s o f pilot s flyin g dissimila r

aircraf t dail y acros s th e Unite dStates
. A helicopte r rout e i s als o no t

limite dt o helicopter s o f

minimu mperformanc e capabilitie s ye t ar e als o safely use ddail y b y hundred s o f pilot s flyin g dissimila r

aircraft
. Gyroplane s ar

e no t les s capabl e tha n helicopter s of fligh t alon g designate d helicopte rroute s throug h majo rpopulatio n centers
. Suc h route s were no t develope d fo rth e purpos e o f hovering , bu t t o allo w efficien t transi t throug h suc h areas . Cruis e speed s o f gyroplane s ar

e comparabl e to , i f no

t faster , tha n man y helicopters
. Unde rcurren t rules , ther e i s n o regulator y basi s fo rdenyin g gyroplane s acces s t o charte d helicopte rroutes
. Perhap s yo u shoul d loo k int o that befor

e makin g blanke t statement s abou t us e o f thos e routes
. You r statemen t

tha t gth e FA A finds that

th e height-velocit y (HA^ ) curv e yo u reference donl y applie s t o [heUcopter ] takeoff

s an d leve l fligh t

with power . I t

i s no t appropriat e t o conside r

th e W W curv e i n a

n autorotativ e landin g a s aresul t o f a n engin e failur e whic h i s th e focu s o f FA R91.119h disclose s a fundamenta l lac k

o f understandin g o f

rotary-win g aircraf

t operations
. I a

msur e tha t

th e FAA Aircraf

t Certificatio n Service , Rotorcraf t Directorate , woul db e mos t relieve dt o no t

hav e t o conside r

height

-velocity limitation s durin g autorotatio n testin g o f helicopters
. Sinc e agyroplan e alway s land s fro ma n autorotativ e descen t

an d th e fligh t

manual s o f

FAA-certificate dgyroplane s alway s includ e height

velocity/graph s —an dahelicopte r i n autorotatio n i s i n essenc e a n inefficien t

gyroplan e —what

i s th e physical basi s for

you r statement ? Not e that

th e paragrap h beginnin g "I t shouldb e note dthat , onc e a steady stat e autorotatio n ha s bee n established.., " o n pag e 1 1 - 4 o f th e Rotorcraf

t Flyin g Handboo k

i s provabl y wrong . Pleas e feel fre e t o execut e alandin g i n ahelicopte r fro mastabl e autorotatio n insid e th e avoi dregion of

it s height-velocit y graph
. Jus t don' t b e anywher e nea r

m e whe n yo u d o it
. You

r discussio n o f

th e us e o f

collectiv e pitc h b y ahelicopte r pilo t t o manag e glid e angl e durin g a n autorotativ e descen t

i s primaril y o f

academi c interes t

sinc e th e objectiv e o f

apilo t durin g suc h a procedur e i s t o maintai n th e minimu mrotor rp mnecessar y a s indicate do n th e roto r tachomete r

t o provid e adequat e rotor

thrus t an d control
. I n an y event , a n autorotativ e descen t

t o alandin g i n a helicopte r i s a n emergenc y procedure ; a n autorotativ e descen t

t o alandin g i

n agyroplan e i s anorma l procedure
. Du e t o th e lowe r dis k loadin g necessar y t o provid e adequat e performanc e i n agyroplan e an d th e fac t tha t it s roto r i s optimize dfor

autorotation , acycli c flar e t o landin g i n suc h aircraf t invariabl y result s i n minimal , if

any , groun drol l afte r

touchdown
. Whe n agroun drol l doe s occur , thi s i s agai n a norma l procedur e fo

r whic h th e gyroplan e i s designed
. Thi s i s no t th e cas e i n ahelicopte r

whic h unles s operate di n a n idea l manne r b y th e pilot , unde r

favourabl e gros s weigh t

an d atmospheri c conditions , wil l ski do r

rol l alon g th e groun dafter touchdow n i s an d highl y pron e t o rol l ove r Fo rhelicopte roperations , th e FAA' s Rotorcraf t Flyin g Handboo k

teache s tha t collectiv e pitc h i s use d t o contro l roto rrpm , no t glid e pat h as yo u stated , whil e glid e performanc e i s a matte r o f airspee d control
. Th e sam e i s tru e fo rglid e managemen t i n a gyroplane , onl y ther e i s n o nee d fo ran y roto rrp m contro l a t all
. As t o th e touchdow n itself , tha t sam e Handboo k advise s tha t groun d rol l fo ra gyroplan e i s routinel y unde r5 0 fee t an d wit h les s tha n 2 0 mp h airspeed , an d that i s withou t consideratio n o f wind
. On e must wonde rwhat yo u mea n b y ver y littl e o r n o groun d ru n i f unde r5 0 fee t doesn' t qualify
. Th e overridin g conce mo f FAR91.11 9 i s t o maximiz e th e probabilit y that afte r a n engin e failure a

n aircraf t ca n lan da s safely a s possibl e whil e minimizin g hazard s t o both it s occupant s an d persons/structure s o n th e ground
. Gyroplane s wer e invente dt o mee t this objectiv e an d hav e alway s outperforme dhelicopter s i n suc h situations
. You

r respons e t o m

y petitio n i s sloppy , unprofessional , an d ultimatel y awast e o f

time
. I wil l refil e thi s petitio n i n ligh t o f th e change s t o FA R91.11 9 an d includ e a s supportin g materia l m

y origina l petition , you r

denia l lette r

an d m y respons e thereto
. Pleas e not e tha t

copie s o f

m y petitio n wil l b e sen t

t o th e organization s liste dbelo w for advisor y purposes . I d o no t

represen t an y o f thes e organization s i

n this matter . Th e overal l them e o

f you rrespons e t o th e petitio n seem s t o b e tha t ther e are ver y fe w standar d airworthines s certifie d gyroplane s at thi s time , an d tha t smal l number s d o no t justify a rul e change
. On e mus t the n wonde rwh y th e FA A ha s a recently-establishe d powered-lif t categor y i n th e regulations , give n tha t ther e ar e exactl y zero suc h aircraf t tha t hav

e receive d standard airworthines s certificatio n worldwide
. I s i t th e FAA' s vie w tha t regulation s t o encourag e developmen t o f som e form s o

f not-yet-develope d rotor-drive n craf t shoul d b e established , whil e regulation s tha t inhibi t practica l an d saf e us e o f othe ralread y existin g form s

### ar

e t o b e lef

t i n place ? Ho

w i s suc h a preferenc e determine d an d justifie d b y th e FAA? I t woul d appea rtha t yo u hav e mad e a n officia l governmenta l determinatio n that ther e i s n o futur e fo rcertifie d gyroplane s t o b e developed , bu t tha t there i s suc h a futur e fo rtilt-rotors , withou t an y Congressiona l authorizatio n t o mak e tha t determination , o ran y marke t dat a i n support
. Th e court s refe rt o suc h action s a s arbitrar y an d capricious
. Th e conclusio n I dra

w fro m you rlette ri s that yo u hol d experimenta l gyroplane s an d thei r pilot s i n ver

y low regard
. 1 share tha t sentiment , bu t i t doe s no t justify denyin g relie f t o thos e o f u s wh o hol d th e highes t pilo t credential s authorize d b y th e FA A an d fl y full y certifie d aircraft
. Sincerely , an-Prerr e Harriso n

cc : Airplane Owner s an dPilot s Associatio n America n Helicopte r

Society Internationa l Carte r Aviatio n Technologie s FA A Aircraf t Certificatio n Service , Rotorcraf t Directorat e Groe n Brother s Aviation , Inc
. Helicopte r

Associatio n Internationa l