a tech stop was very rare,” says
Thompson. “By adding winglets,
we were able to meet the long-range
requirements for them. Winglets
always give airplanes ‘legs.’”
Winglets, in effect, increase an
aircraft’s wingspan. “But you don’t
have to increase it as much to get
a pretty good performance bump,”
says Mike Stowell, executive vice
president-engineering, Aviation
Partners Boeing, a joint venture
between API and the airframe man-
ufacturer to develop and produce
tip devices, including spiroids, or
“looped,” wing tips for commercial
aircraft. “You get a big perfor-
BLR Aerospace winglets on the company’s Super King Air 200 were STC’d in 2005. Winglet kits were delivered to
mance improvement, but you don’t
customers soon after the approval.
have such a space impact on your
gates, ramps and hangars.”
Good Big or Small
Winglets are not just slapped on
the end of a wing, but are finely
tuned pieces of aerodynamic art.
Each one is individually crafted to
the particular aircraft and wing on
which it will be mated. According
to BLR Aerospace, these details
are equally important when devel-
oping winglets for piston and tur-
boprop aircraft. Located near API,
in Everett, Wash., BLR Aerospace
produces performance-enhancing
modifications for both military
and civil fixed-wing aircraft and
tailboom strakes for rotorcraft.
“Every aircraft wing is different
and every situation is different
so every winglet design has to be
different,” explains Dave Marone,
BLR’s vice president-sales and mar-
keting. For example, the weight of
winglets is critical and calculated
to counteract the greater bend-
ing moment created as a result of
lengthening the wing. Surprisingly,
winglets for the Beech Duke are
slightly heavier than those for the
larger King Air.
“You start with computational
fluid dynamics – computer model-
ing methodology,” Marone adds.
“Once you have a model created,
you move on to smoke and wind-
tunnel testing…to validate what
20 Aviation Maintenance |
avmain-mag.com | Oct/Nov2009
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56