| Wings
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| Article from the May 2001 edition of the GACH newsletter
Wings
In aviation, we learn by doing, but also by accident. When one occurs, as happens with all too much frequency, it is useful to delve into the causes and see if there’s anything there that might keep us safer. And, when doing that, conjecture won’t do. You really need the expertise of the experts. And that’s precisely what you have available at the seminars. Often, the actual cause may be quite different from the apparent one, and preliminary accident reports, in which the cause is listed as “failure to obtain/maintain adequate clearance from…” or “failure to obtain/maintain sufficient airspeed” really do little to educate us. George Pettersen of the NTSB brings true insight derived from thorough investigations and his presentations are always fresh and very informative. And there’s more—much more. Timely piloting and maintenance topics abound and time you spend at the event will be well worth it. Beautiful Wings Have you ever had the opportunity to study a wing at work over an extended period of time? A wing is a thing of function, and sometimes of real beauty. Who among you isn’t struck by the grace of a Spitfire’s elliptical wing? It’s not just beautiful—it’s efficient and exhibits marvelous flying characteristics. I imagine that’s why that shape was chosen for the wing on my CAP-10. A wing has to be many things. It must produce the right combination of lift and drag to suit the aircraft’s mission; provide adequate support and geometry for various flight controls; and it may also need to be strong enough to support engines, landing gear, fuel tanks and even ordnance. If the range of functions it must perform is broad enough, it may even need to change its shape, and thus, characteristics in order to meet seemingly incompatible requirements of take-off, climb, cruise and landing phases of flight. The wing of the Boeing 767 is truly a thing of beauty--an absolute marvel,
functionally and esthetically. I just came back from a trip to the
mainland on a very new Boeing 767-400 and had several hours to while away.
I was seated by the window right over the wing (in what was one of the
most miserable excuses for a passenger seat I’ve ever experienced—but,
I digress). Having already seen the movie on the way out, I opted
to watch the wing do its thing. And this wing is high tech.
Unlike the wings of most airliners I’ve seen, this one is flawlessly smooth
with no visible rivets at all on the upper surface, and all panels, flight
controls, slats, and spoilers fit almost seamlessly. The smoothness
is broken only by seven relatively small vortex generators just aft of
the leading edge slats. The wing is swept and tapers to a slender
tip, arcing gracefully upward as it develops lift. It’s a large wing
for a large airplane, but it evokes a glider’s wing as you look out along
its considerable span. At the tip is a semi-winglet to modify the
flow of the tip vortex and thus, reduce induced drag.
Is there a down side to this beautiful wing? Only if you are following too closely. The 757/767 series aircraft have developed a well-deserved reputation for putting out a powerful set of vortices—much more so than the weight of the aircraft would suggest. As the airlines try to cut operating expenses, many older “heavies” are going to be replaced by 757/767’s. Delta, TWA and soon, Hawaiian will all be shedding their DC-10’s and L-1011’s for the big twins. Watch out! Recent research shows that the vortices do not always descend and move away from the aircraft’s flight path. Sometimes they maintain their altitude, and they are even known to “bounce” off the runway back into the air. The ugly fact is, they are actually a bit less predictable than previously believed, and more caution is clearly advisable. When operating anywhere near one of these beautiful birds, be ready for the bite and have a plan in hand. Some upset training wouldn’t hurt, either. Aviator’s Aviator
South Practice Area The South Practice Area on O’ahu is shrinking due to encroaching development and is becoming more dangerous to aviators. This was the topic of the last Aviation Safety meeting at the FSDO. The participants pooled their wisdom and experience and came up with the following recommendations: a. Show a landing light when in the practice area if possible.These are interim recommendations to increase safety until any more permanent procedures are implemented. In addition, please remember that transitions to the North Shore from HNL should be at 2,000’ MSL, east of Wheeler, weather permitting, and southbound transitions from the North Shore to HNL at 2,500’, just west of Wheeler. Instructors should insure students and renter pilots are familiar with local checkpoints. Specifically, the pineapple stand (labeled on the Class B chart as such) is known as “Dole” and the intersection of Wilikina Drive and Dole Plantation Road northwest of Wheeler is known as “Pineapple Intersection”. Harbor View is the intersection of H1 and Kunia Road. We really don’t need another mid-air and it is vital to fly akamai with your head up. Hana Happening
Pearl Harbor, The Movie
Oshkosh Bound?
Be careful out there.
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