V.C. Aircraft Certification

The proposed rule would amend part 121 to require each 10- to 19-

passenger seat airplane that is to be operated in scheduled operations

and for which an application for type certification is made after

March 24, 1995, to be type certificated in the transport category.

Affected commuter airplanes are type certificated under the

requirements of part 23.

In Notice 95-5 the FAA stated its intent to review the standards

of parts 23 and 25 to see if the level of safety intended by part 25

could be achieved for those airplanes with a passenger-seating

configuration of 19 or less through compliance with a particular

standard of part 23 or another standard, in lieu of the corresponding

standard of part 25. On completion of that review the FAA stated its

intent in future rulemaking to consider amending part 25 as necessary

to accommodate type certification in the transport category of certain

types of airplanes previously type certificated in the commuter

category.

The FAA also proposed that airplanes configured with 10 to 19

passenger seats already in service or manufactured in the future under

an already existing part 23 commuter category type certificate would

have to comply by specified compliance dates with certain performance

and equipment requirements in part 121. These performance and

equipment requirements are discussed later in this preamble.

In Notice 95-5 the FAA included a table that set out a list of

potential modifications that were being considered for application to

airplanes having a passenger-seating configuration of 10-19 seats that

were type certificated in the commuter category (or a predecessor) if

the airplanes are to be used in scheduled operations under part 121.

The table included a column that indicated that for 12 of the 38

issues addressed, the FAA had determined that any required upgrade

should apply only to airplanes manufactured under a type certificate

for which application is made after March 24, 1995. Since these 12

issues will be the subject of a future NPRM, the FAA is not addressing

specific comments on the substance or cost of these issues in this

document.

Comments: ALPA fully supports the proposal to require newly-

designed airplanes to comply with the standards of part 25 and also

supports continued use of commuter category airplanes. The commenter

does not, however, concur that airplanes type certificated under part

23 normal category (i.e., pre-commuter category) should be permitted

to remain in operation with more than 10 passenger seats, even in

non-air carrier service. ALPA appears to base its position on

differences in performance requirements between commuter category and

the predecessor normal category standards.

American Eagle supports the proposed rulemaking and states that,

"while there may be limited circumstances when aircraft design and/or

manufacture may preclude or delay compliance with FAR part 121 or FAR

part 25, cost and weight considerations should not be an acceptable

barrier to the increase in safety which is derived from applying the

higher standards of aircraft airworthiness, airline operations and

passenger safety which those regulations provide."

In contrast, six other commenters do not believe that any

propeller-driven airplanes with 10 to 19 passenger seats should be

required to meet the transport category standards of part 25.

Although the commenters' reasons vary, the comments focus on three

basic issues: (1) commuter category standards are appropriate for

airplanes of this class; (2) there is no evidence that safety would be

enhanced by requiring future airplanes to comply with part 25; and (3)

the cost of complying with part 25 would be prohibitive.

Similar comments concerning recertification of existing part 23

airplanes under part 25 were also offered, apparently under the

misunderstanding that airplanes already type certificated, or

derivatives of those airplanes, would have to be recertificated under

part 25.

Some commenters believe that the airplane certification issue is

of such magnitude that it should be held in abeyance for a separate

future rulemaking program. In this regard, the commenters assert that

extensive changes to part 25 would be needed to accommodate the

airplanes otherwise certifiable under part 23 commuter category and

that those changes would entail a considerable expenditure of FAA

resources. They further believe that any such changes should be

subject to harmonization with corresponding standards of the European

Joint Aviation Requirements (JAR).

Several commenters cite the FAA's 1977 proposal to require all

airplanes used in air carrier service to meet part 25 transport

category standards. That proposal was later withdrawn. According to

commenters, the part 23 standards of that era were considerably

different from those of today's part 23 commuter category. The level

of safety expected by the public today is much greater than that

tolerated in 1977.

A number of other commenters address the proposed retrofitting of

existing part 23 normal and commuter category airplanes to meet

certain part 25 standards. Those comments are addressed in the

section-by-section portion of this preamble (Section VI).

One commenter has developed and produces a unique propulsion

system in which two turbine engines drive a single propeller through a

common gearbox. In addition to the installations already being made

in existing airplanes, the commenter anticipates a future installation

of this system in an airplane of entirely new design. Since any new

model would have to be type certificated under the provisions of part

25 in order to be eligible for operation under part 121, the commenter

requests that part 25 be amended to accommodate airplanes with this or

similar propulsion systems.

FAA Response: Rather than forcing the retirement of part 23

normal category airplanes, as recommended by ALPA, the FAA proposed in

Notice No. 95-5 to permit their continued use in air carrier service

provided certain changes were made on a retrofit basis to enhance

their level of safety. Banning those airplanes would be extremely

costly, but most importantly could result in an unintended safety

decrement. Indeed, the FAA's analysis indicates that moving too

quickly on the imposition of part 121 standards could have the

unintended effect of lowering the level of safety because operators

would not be in a financial position to quickly obtain new airplanes

and currently there are not enough replacement airplanes available

that meet the higher standards. The result could be a shift from 10-

to 19- seat turbopropeller airplanes to 9-seat or less reciprocating

engine airplanes, which have an even higher accident rate.

The six commenters' assertions that commuter category standards

of part 23 are appropriate for airplanes of this class and that there

is no evidence that safety would be enhanced by type certification

under part 25 are, to a certain extent, correct. Through a number of

recent amendments and pending amendments, the level of safety

established by the commuter category has been and is being enhanced

considerably. In many instances, commuter category airplanes must

meet standards that are the same as, or very similar to, those of part

25 transport category. Requiring future 10- to 19- passenger seat

airplanes to be type certificated under part 25 would complete this

effort to ensure that these airplanes used in air carrier service meet

the same aircraft certification standards as the larger airplanes.

In response to comments that part 23 airplanes could not be type

certificated using part 25 standards, the FAA notes that it did not

propose in Notice No. 95-5 that part 23 normal or commuter category

airplanes presently in operation would have to comply with part 25

standards for type certification. Instead, it proposed that part 23

airplanes that will be required to be operated under part 121 will

have to comply with certain part 121 equipment and performance

requirements.

In response to the individual comment on a unique propulsion

system, although the commenter's request is beyond the scope of this

rulemaking, it will be considered during the review of part 25

discussed above.