Selected photos from:

Boeing 727 FAA Certification Flight Test /
Research and Development Program


This is a drag reduction program for a Boeing 727-100 involving winglets and wing re-contouring (flap and slat system modifications). Significant drag reductions were produced, and the program was awarded an FAA STC. Alligator had responsibility for all aspects of installation of test equipment and data acquisition for the program, involving 80+ channel digital, analog, low-speed and high-speed data acquisition. (September 1990 - March 1991)


Boeing 727-200 with Valsan winglets


Airflow visualization tufts viewed from chase plane


Inside tufts viewed from cabin


Nose boom installation for pitot pressure, static pressure,
angle of attack and angle of side-slip measurement


Strain gauges installed on horiz. stabilizer spar
for measuring stall buffet effects on horiz. tail


Weighing the Boeing 727


Weighing kit load cell


Ground vibration test (GVT) shaker installation on wing tip


GVT test equipment


Mirror pod for visualization of horiz. tail buffet. (In an ideal world, we would have installed miniature external cameras to directly record horiz. tail buffeting. However, the test requirements were established at the last minute and we came up with this solution in two hours and got the test data that same day. The next two photos show further detail of this innovative approach.)


Back side of mirror pod


Video camera used for recording horiz. tail buffet via external mirrors


No-cost (borrowed) floor-dry used to create gross weight conditions


Data system, created and operated by Alligator for Test Instrumentation, Inc. (circa 1991)


Simulated ice shapes installed on wing tip and winglet to
demonstrate flight characteristics under icing conditions


Ron co-piloting 727 during winglet test program


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