Why weren't wingtip devices used on airliners since day 1?

Gulfstream GII's tried wing tip tanks, until they figured out the drag was not worth the extra fuel. The early ones also had a huge stall fence.

API winglets came later on with a 7% increase in fuel efficiency according to this artilce on Joe Clark who co-founded API in 1991 with Dennis Washington. they mention the work with Gulfstream, Boeing and others.




http://www.airportjournals.com/Display.cfm?varID=0212004

 

And FYI, the 767-400 uses the raked wingtips as well.

One useful purpose for the blended winglets: advertising, of course! On the night flights I've flown on AirTran's 737s, they sometimes keep the winglets illuminated for the entire flight!

 

Al Paulsen was also part of the Aviation Partners group for the G-II.

Jeff

 

The fuel burn improvement on the 737 is very, very real.

Jeff

 

Okay, enough. They are talking about a Douglas airplane so I guess that's close enough. It has wings and a tail.
I don't fly them and I don't design them, I just work at the place that builds them so I'll just shut up and let the "Experts" tell us how it really is.

 

The entire idea of the winglets was to emulate a wing of infinite length, thus lowering drag and turbulence at the wing tips. There is more than one way to do this, as Spasso noted. We used to sweep the wings on fighters, too, until better wing designs negated most of the advantages of doing so without any of the penalties of weight and complication. Winglets are just one possible solution, and since they were easy to graft on existing wing designs, are in widespread use. That use will decline in the future as simpler, more elegant solutions to reduce wingtip drag are implemented as part of a total wing design.

Taz
Terry Phillips

 

Taz, I think the six is still the fastest single engine aircraft. If I remember the jet they used to set the record was just a standard "line" jet with no mods or anything special done to it. I missed flying it by a few years, bummer!

 

Jim- Affirmative, the J-75 could really push a 106 or 105 along. The 106 broke the 104's record of 1404 mph. Then along came a Mig-25 variant, the E-266 IIRC, and blew them all away until the SR and its relatives came long.

In the early days, we used F-106s for DACT to emulate Mig-21s. They were a bit bigger, but turn characteristics were similar (energy bleeding very fast at max AoA) and they had a great T/W ratio. They even updated them with semi-bubble canopies and updated avionics just before, as usual, retiring them. Pilots loved them except for sitting Zulu alert in some really nasty areas while wearing full poopy suits. Too bad you never got to try one. They even had F-106Bs that were dual control so I might have been able to con a ride.

I loved the sound of the afterburner with water-cooling lighting. Sounded like a very loud gunshot or a medium size explosion, which was closer to the truth.

Taz
Terry Phillips