AEROSPACETESTINGINTERNATIONAL.COMAPRIL 2015 | 59
F-35 latest developments z
S
ince December 2006, the F-35
Lightning II has surpassed
25,000 combined flight hours
with 16,200 hours in F-35 military
fleet aircraft and 8,950 hours of system
development and demonstration
testing. Much of that testing has been
conducted by the F-35 Lightning II
Integrated Test Force (ITF) assigned to
Air Test and Evaluation Squadron (VX)
23, based at Naval Air Station Patuxent
River, Maryland.
Operating at a high tempo is
routine for the Pax River ITF’s cadre of
military, government and contractor
testers. In the span of less than six
months, they successfully conducted
two high-profile test evalutions on
opposite coasts of the USA and began
preparations for additional high-
visibility testing, yet again on both
sides of the country.
On September 29, 2014, the ITF
deployed a team of 40 testers to the
McKinley Climatic Laboratory (MCL),
the world’s largest environmental
testing chamber. The 96th Test Wing,
a US Air Force Materiel Command
unit, operates the MCL at Eglin Air
Force Base in Fort Walton Beach,
Florida. For six months, the Pax River
ITF Climatic Test team and key
members of the Edwards ITF have
capitalized upon the MCL’s proven
capability to recreate nearly every
weather condition on Earth as theyAs the F-35 Lightning II completes a whole raft of flight test
trials, Aerospace Testing International takes an exclusive
look at the involvement of the Integrated Test Force (ITF) in
this stage of the fighter’s complex multirole developmentBY SYLVIA PIERSONLightning II
LEFT: An F-35B
Lightning II short
take-off/vertical-
landing (STOVL)
variant of the
Joint Strike Fighter
is currently
undergoing climatic
testing at McKinley
Climatic Laboratory
(MCL) at Eglin AFB.
An icing cloud test
calibration fixture
has been installed
within the climatic
chamberassessed the performance of aircraft
BF-05, the short take-off/vertical
landing (STOVL) variant, in a wide
array of temperatures and
meteorological conditions. Testers put
the aircraft through extremes such as
-40°F/C up to 120°F (48.8°C) and
featured wind, solar radiation, fog,
humidity, rain intrusion/ingestion,
freezing rain, icing cloud, icing
build-up, vortex icing and snow.
By placing BF-05 onto a purpose-
built frame, test pilots were able to
‘fly’ a standard profile in accordance
with defined test sequences. This
profile featured a normal start-up, a
VSBIT (vehicle systems built-in test)
to check the onboard systems, a
simulated short take-off, a climb out,
full afterburner runs in conventional
mode, and a simulated vertical landing.
Each meteorological condition was
fully tested and featured 60% ground
operations and 40% flying, including
engine runs and simulated flight in
both conventional and STOVL modes.
Testers also ensured the collection
of accurate and representative data
during the icing evaluation by
installing additional F-35A and
F-35C icing detector probes according
to each variant’s design.
“This type of testing doesn’t happen
every day,” says US Navy test pilot
Cdr Tony ‘Brick’ Wilson. “What the
McKinley team has pulled off at Eglin