Avionics News September 2022 - 33

Why does §21.17(a) versus §21.27(b) matter, and does it matter?
A few key issues arise with a §21.17(b) determination:
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Airman qualifications.
Operational rules.
International harmonization/aircraft acceptance.
Project timelines.
Airman qualifications
How will airmen be qualified to fly these powered-lift aircraft?
After all, there are no powered-lift civilian aircraft in which a pilot
can become qualified to fly these aircraft, and the FAA has yet to
promulgate airmen certification standards for powered-lift, even
though industry presented draft ACS documents to the FAA several
years ago through the Aviation Rulemaking Advisory Committee.
The International Civil Aviation Organization provides language
for this issue in Annex 1, saying a pilot can
be qualified by holding either an airplane
or helicopter rating and adding poweredlift
type rating for the specific aircraft type.
Not only does this allow a properly trained
pilot to fly the aircraft, but it prevents
" privilege bleed " - that is, the ability to
train and qualify in one aircraft type and use
that to qualify in one very different aircraft
type. Aircraft caught in the powered-lift
definition not only have different propulsion
methods but have different human/machine
interfaces, including flight controls and
avionics capabilities.
" ICAO guidance provides the framework
that has global recognition and acceptance
to enable initial operations, including airmen qualifications, of
new powered-lift category aircraft, " said Walter Desrosier, vice
president of engineering and maintenance for the General Aviation
Manufacturers Association. " The FAA needs to look at applying
that guidance within its own regulatory structure. This provides a
pathway not only to implement these operations in the U.S. but an
approach that's ready for global recognition and acceptance. "
The FAA suggests a special federal aviation regulation will
provide " alternate eligibility requirements to safely certificate
initial groups of powered-lift pilots, " according to the Unified
Agenda of Regulatory and Deregulatory Actions, which lists
all regulatory and deregulatory activities under development
throughout the federal government. This SFAR will apply to
allow powered-lift aircraft, not just eVTOL. The AgustaWestland
AW609, a tiltrotor VTOL, will also be covered in this SFAR.
The diversity of the expected VTOL fleet means type-specific
training of some sort is necessary to ensure safe operations. A type
rating added to an existing airplane or helicopter rating makes
perfect sense. It also gives the regulator - the FAA - authority
and oversight over the training requirements. In practice, this
authority will be exercised during the Flight Standardization Board
report, and oversight will be exercised through local FAA offices
overseeing operators and training providers.
Operational rules
Part 91 and other operational rules, including Part 135, which
many operators intend to use for commercial operations, include
airplanes and helicopters. How will a new category of aircraft fit
in this regulatory regime, developed decades before powered-lift
aircraft were even conceived?
SOME OEMS ARE WELL
BEYOND THE DREAMING
STAGE. THESE OEMS
ARE FLYING FULL-SCALE
PROTOTYPES, DEVELOPING
AND TESTING PILOT
TRAINING PROGRAMS,
AND BUILDING THEIR
BUSINESS MODELS.
ICAO has a solution for this, too. ICAO Guidance Doc 10103
states, " While sharing aeroplane characteristics, tilt-rotors are most
closely aligned with helicopters due to their ability to sustain flight
at low speed, as well as to take off and land vertically. Therefore,
helicopter SARPs should be used as the
basis for tilt-rotor operations. Where
deviation is required from helicopter SARPs
to cover other aspects of flight, this manual
provides guidance and reference to relevant
aeroplane SARPs. "
Introductory text in Doc 10103 indicates
that while the document specifically refers
to tilt-rotors, ICAO notes tilt-rotors are part
of the powered-lift category for aircraft
and this manual should be used as a basis
for other civil powered-lift aircraft.
Essentially, this language would allow
operational rules to be designated for these
aircraft based on capabilities.
Does a powered-lift aircraft with a
glide ratio similar to a light airplane need floats to fly over
water, within gliding distance of shore? No. Airplane rules are
appropriate for that scenario.
On the other hand, should an aircraft capable of taking off and
landing vertically be permitted to use a heliport? Absolutely, so
long as the surface is of appropriate size to ensure safe operations
for that particular aircraft.
International harmonization/aircraft acceptance
The FAA holds bilateral agreements with a number of aviation
authorities to ensure an aircraft type certificated in one country is
recognized in another. Unfortunately, most aviation authorities do
not have a corresponding §21.17(b), special class category.
How will the aviation authorities review and accept a special
class aircraft? This definition is an issue that requires additional
discussion with international aviation authorities but is not
insurmountable.
Continued on following page
AVIONICS NEWS * SEPTEMBER 2022 33
Avionics News September 2022

Table of Contents for the Digital Edition of Avionics News September 2022
