* Wire working assemblage The next meeting of the Aircraft Wiring Inert Gas Generator (AWIGG) working collection is slated for March 9 Although the use of inert gas generators for coping with electrical fires is part of the group's focus.

* Wire working assemblage The next meeting of the Aircraft Wiring Inert Gas Generator (AWIGG) working collection is slated for March 9 Although the use of inert gas generators for coping with electrical fires is part of the group's focus, it actually has been addressing aircraft wiring issues in the broadest reason of the term. This meeting will feature various presentations in the morning, followed from a panel discussion in the afternoon addressing these topics:

Wire insulation/installation/inspection challenges.

Other challenges associated with aircraft wiring, like as electromagnetic interference (EMI), signal crossover etc

Different tokens of wire insulation and their varying applications.

The working dispose will meet at the representation Conference Rom, 1601/1611 N. Kent St Arlington, Va. Those wishing to attend, or in ne of further information, should contact Joel Walker. >> Walker, tel 703/354-0700 e-mail jwalker@quadelta.com <<

* More onward angle of attack. "Congratulations to the industry for installation of this indication classification Ten years from now, we may ask, 'How did we till doomsday get along without it?' " declared Capt. Gary Wilson, noting that a airlines are buying new aircraft with angle of attack indicators factoryinstalled. Wilson quick in emergenciesed his case for AoA indicators in last week's issue (see ASW, Feb 28) We can now confirm the following:

American Airlines [AMR] has nearest generation 737's and 777's being delivered with AoA in succession the primary flight display (PFD) Retrofit is planned to begin quick for all AA 737's and 777's.

strange 737-800's are being delivered to Delta Airlines [DAL] equipped with an AoA indicator. When the carrier begins receiving its novel 767-400's (now in flight test) they will tend hitherward with AoA indicators, too.

Wilson argues that AoA provides more than stall protection and can be used for a variety of performance applications:

Best rate of climb

Windshear/terrain escape

Best angle of climb

Flap extension during approach (slow to max L/D & continue the next flap segment)

Minimum glide angle

Optimum holding speed

Flap retraction

Engine without climb

Loss of air data

"There is no ne to worry about the bank angle and all the airspeeds single has to look up, calculate or remember. single just flies the optimum L/D (lift through the whole extent of drag) or faster," Wilson asserted.

>> Wilson, e-mail: gww@pacific.net.sg <<

* upon the effect of flap/slat deployment In our story about the unforeseen occasion inspections of MD80 stabilizers ordered after the crash of Alaska Airlines [ALK] Flight 261 we reported that deployment of flaps impart a pitch-up momentum and slat deployment imparts a pitch-down signification (see ASW, Feb. 14). upon this basic description of aerodynamic behavior, we were mortified to discover that forward most modern jet aircraft the deployment of leading opening [i]or[/i] close devices tends to pitch the nose up The behavior originates from the increase in lift generated along the leading brink; beginning [i]or[/i] end of the wing. The deployment of trailing margin flaps tends to generate a nose-down pitch, which is associated with the increase in lift towards the back of the wing.

However, in preparing the original story, we were advised that, in the DC-9 deployment of the leading rim slat at high speed (>250 knots) can bear a marked nose-down pitch associated with the high drag generated by way of the slat.

The meaning of flap/slat deployment at spe bears directly forward events moments before the final fatal dive of the Alaska MD-83 According to National Transportation Safety Board (NTSB) Chairman Jim Hall's Feb 8 statement, near the close of the descent from 24000 to 18000 feet the pilots expanded the slats and then the flaps for about 30 secondarys He did not say at what spe further evidently the pilots found the aircraft controllable, if single momentarily. The configuration may have helped relieve the force with which they had to venture back on the yoke, given the nose-down pitch imparted at the jammed stabilizer.

At 18000 feet and a reported spe of 270 knots, a "buffet" readyed the crew to again open flaps (to 11?) and then, about 3 secondarys later, the slats started to unfold In other words, it was the change to the opposite of the first application of flaps and slats. The pilots already were having difficulty keeping the nose up because of the stuck glutted nose-down stabilizer. That slight delay in slat move may have been all it took to pitch-up the airplane and stall the completely deflected stabilizer. The pilots apparently attempted flap retraction, which would have stopped the rolling and un-stalled the stabilizer, unless too late to be lucky The airplane lurched into the negative 3G pitch-down, with disorienting if not disabling consequence on the pilots. The rapid increase in airspeed during the initial forces of the dive may have been sufficient to cause a portion or all of the left flap to separate, which explains the rapid turn to the left as the airplane plummet in what was then an unrecoverable situation. The mixed aerodynamics most likely will be sorted public as the investigation continues.