03/01/201 0 12:5 5 816329410 6 SA D PAG E 02/0 4

SJbechttaf t

Hawha r Baaehcraf

t Corporatio n P.O
. Bo x 9 5 Wichite , Kansa s 67201-008 5 US

A In Repl y Refe r

to : 940-2010-0068 4 

## 1 3 Actio n Februar y 16,201 0 n Inf o Onl y FA A Projec t

No. : AT5075WI- A Cert
. Projec t

No. : 390-2 2 Federa l Aviatio n Administratio n Ki mSmith , Manage r Smal l Airplan e Directorat e Kansa s City , Missouri Subject ; Reques t

for a n Exemptio n t o 1 4 CFR§23.783(f)(l) , Amendmen t 23-4 9 Reference : (1 ) HB C Letter , date dJul y 23 , 2008 , lette r 940-2008-05320 , Submittal o f Certificatio n Pla n 392E283,'582 , Revisio n 1 (2 ) HB C Letter , date dAugus t 25 , 2008 , lette r

940-2009-07531 , Submittal of Certificatio n Plan 392E283582 , Revisio n 2
Dea r Ms
. Smith : Thi s lette r i s areques t

fo r a n Exemptio n to 1 4 CF

R§23.783(f)(I ) fo

r th e Mode l 390-2
. Th e regulatio n 1 4 CFR§23.783(f)(l ) state s "( 0 I " addition , for commute r

categor y airplanes , th e followin g requirement s apply : (I ) Eac h pa;ssenge

r entr y doo r mus t qualif y a s afloo r

leve l emergenc y exit
. Thi s exi t mus t hav e arectangula

r openin g of

no t les s tha n 2 4 inche s wid e b y 4 8 inche s high , wit h come r radi i no t greate r tha n one-thir dth e widt h of th e exit. " HB C i s requestin g relie f

fromcomplianc e t o 1 4 CFR§23.783(f)(l ) a s amende db y Amendmen t

23-49
. Enclose di s Hawke r

Beechcraf

t Corporation' s petitio n for exemption
. I f you hav e question s o r

concern s pleas e contac t

Vicki e Gof

f a t 31 6 676-6927
. Sincerely , HAWKE RBEECHCRAF T CORPORATIO N

I Davi dBemstorf

, Vic e Presiden t Safet y an dCertificatio n DB/ve g Amched ; HB C Petitio

n for Exemptio n03/01/201 0 12:5 5 81&329410 6 SA D PAG E 03/0 4 Attachmen t

t o lette r 940-2010-0068 4 Page 1 o f 2 

## Petitio n fo rExemptio n Requestor : Hawke rBeechcraf t Corporatio n

970 9 Eas t Centra l P.O
. Bo x 8 5 Wichita , K S 67201-0085 , US A Subject : Complianc e Relie f fro m 1 4 CF R 23.783(f)(1 ) fo rPassenge rEntr y Doo r Project : Hawke rBeechcraft , Mode l 390-2 , FA A Projec t No
. AT5075WI- A References : 1 ) HB C Letter , date d Jul y 23 , 2008 , lette r940-2008-05320 , Submitta l o f Certificatio n

Pla n 392E283582 , Re v1 2 ) HB C Letter , date d Augus t 25 , 2009 , lette r940-2009-07531 , Submitta l o f Certificatio n Pla n 392E283582 , Re v2 Issue : Exemptio n fro m 1 4 CF R 23.783(f)(1 ) Amendmen t 23-4 9 Summary : 1 4 CF R23.783(f)(1 ) states : "(f ) In addition , fo r

commute r

categor y airplanes , th e followin g requirement s apply : (1 ) Eac h passenge r

entr y doo r mus t qualif y a s afloor

leve l emergenc y exit
. Thi s exi t mus t hav e arectangular openin g o f

no t les s than 2 4 inche s wid e b y 4 8 inche s high , wit

h come r radi i no t greate r tha n one-thir dth e widt h of th e exit. " HB C i s requestin g relie f

fro mcomplianc e t o 1 4 CF R23.783(f)(T ) a s amende db y Amendmen t 23-49
. Hawl^e r Beechcraf

t Corporatio n (HBC ) request s a n exemptio n for

th e Mode l 390-2 , FA A Projec t Numbe r AT5075WI-A , wit

h respec t t o th e minimu mexi t

openin g of

th e floo r leve l entr

y doo r specifie din 1 4 CF R $23.783(f)(t ) o

f th e certificatio n basis
. Th e Mode l 390- 2 entry doo r ha s basi c dimension s an da n openin g are agreate r

tha n tha t define db y th e minimu mdimension s require db y 1 4 CF R§23.783{f) ( 1)
. However , ther e ar e severa l localize dprotrusion s int o th e minimu mwidt h openin g o f

th e doo r cause db y doo r locking/latchin g components . HB C wil l conduc t a n egres s tes t

(throug h cabi n door ) pe r

1 4 CF R§23.803(a)
. HB C propose s tha t

th e protrusio n withi n th e passenge r doo r entry openin g widt

h of 2 4 inche s wil l no t

affec t th e emergenc y evacuatio n o f th e maximu mnumbe r

o f occupants . Reaso n fo rRelie f Sought : Applicatio n fo r

an amende dTyp e Certificat e ha s bee n mad e for th e Mode l 390-2 , Th e Mode l 390-2 i s a6 passenge r commute r

categor y aircraf t intende dt o b e operate dfor busines s an dcorporat e travel
. Th e desig n of th e doo r ha s no t change dfro mth e original Mode l 39 0 desig n an dn o ne w protrusion s ar e bein g introduce d int o th e doo r

openin g area . Althoug h thi s ne w derivativ e mode l i s bein g certifie din th e commute r category , th e numbe r

o f passenger s for

whic h i t i s bein g certifie d( 2 cre w an d6 passengers ) i s no t changin g fromth e origina l Mode l 39 0 certification
. Th e Mode l 390- 2 entry doo r ha s basi c dimension s greate r tha n th e minimu mrequire db y 1 4 CF R§23.783(f)(1)
. Th e total are ao f th e Mode l 390- 2 cabi n doo r openin g minu s th e are aoccupie db y localize dprojection s i s greate r than th e are ainscribe db y th e minimu mdimension s defme d b y 1 4 CFR§23.783(f)(1) , however , th e minimu mwidt h dimensio n canno t

b e me t du e t o th e protrusions
. Publi c Interest : Complianc e t o 1 4 CFR$23.783(f)(l ) woul dhav e n o mea-surablc improvemen t on safety
. Al l owners/operator s wil l b e traine dregardin g th e operatio n o f th e passenge r

emergenc y exit
. Th e trainin g mus t b e acceptabl e t o th e FA A ACQ , Passenge r briefin g card s wil l b e on boar dt o explai n th e operatio n o f th e exit
. Occupanc y of

th e airplan e i s restricte dt o maximu m2 cre w seat s an d6 passenge r seats . In accordanc e wit h03/01/201 0 12:5 5 816329410 6 SA D PAG E 04/0 4 Attachmen t

t o lette r 940-2010-0068 4 Page 2 o f 2
1 4 CFR§23.803(a) , an evacuatio n demonstratio n throug h th e cabi n doo r wil l b e conducte dutilizin g th e maximu mnumbe r

of occupant s define di

n th e TCD S fo

r th e Mode l 390
. 

### Effect s o n Safety : HB C believe s tha

t there wil l b e n o increase deffec t o n safet y b y complyin g wit

h minimu mwidth
. Th e Mode l 390- 2 ha s a

n increase dgros s weigh t

ove r th e original Mode l 39 0 bu t th e seatin g capacity , cabi n an ddoo r dimension s remai n th e sam e a s th e Mode l 390
. Servic e history ha s bee n reviewe dan dn o issue s hav e bee n show n wit h th e cabi n doo r

evacuatio n du e t o th e protrusion s for th e Mode l 39 0 i

n any accidents/incident s wher e egres s wa s demonstrated
. Base do n original certificatio n of th e Mode l 39 0 an dservic e history , th e passenge r entry doo r

certificatio n shoul dremai n vali dfo r

certificatio n o f

th e Mode l 390-2
. 

### Petitio n summary : I n accordanc e wit

h CF R§21.21(b)(1) , HB C request s a n exemptio n t o th e requirements outline dabov e for th e Hawke r Beechcraf

t Mode l 390-2
. Th e Mode l 390- 2 entry doo r ha s basi c dimension s greate r tha n th e minimu mrequire db y 1 4 CFR §23.783(f)(l)
. Th e total are aof th e Mode l 390- 2 cabi n doo r openin g minu s th e are aoccupie dby localize d projection s i s greate r

tha n th e minimu mare arequiredby 1 4 CF R§23.783(f) ( I) , however , th e minimu mwidt h dimensio n canno t

b e me t a t discret e point s du e t o th e protrusions
. HB C wil l conduc t

a n egres s tes t

pe r 1 4 CFR§23.803
. Th e egres s tes t wil l demonstrat e th e 390- 2 Entry Wa y dimension s provid e enoug h ope n are aa s t o allo w saf e exi t o f th e airplane
. Servic e histor y ha s bee n reviewe d an dn o issue s hav e bee n show n wit h th e cabi n doo r

evacuatio n du e t o th e protnision s for th e Mode l 39 0 i

n an y accidents/incident s wher e egres s wa s demonstrated , HB C propose s that

a n exemptio n b e base do n th e Mode l 390- 2 entry door' s basi c dimension s an dope n are a i n exces s of

th e minimu mrequire db y 1 4 CF R§23.783(f)(l ) an don th e successfu l demonstratio n o f egress .