And Still Promoting Aviation Safety!
ROBERT RESER
Bob is typed in B727, B757, B767, B747-400, DC-10 and B-25. He flew USAF and Air National Guard transport (C-123), observer (O-2), and jet fighter (RF-84, F-89, F-102) aircraft for 20 years, and he flew commercial airliners large transports for 30 years. He also holds USAF Navigator and Radar Observer ratings. But you can read more of his story
HERE, as he was my Friday Flyer in 2014!
What has Bob been doing over the previous three years? He's continually updating his book and sharing his passion for flight. He also offers his work for free on his website too! An amazing aviator giving back to the world. Thank you Bob!
Excerpt From Bob's book:
High-Altitude Stall High-Speed Recovery
Operation at very high altitudes often results in minimum indicated-airspeed spread between mach buffet and stall. This then requires pilots to maintain special awareness of flight conditions that may cause undesired change to the indicated-airspeed.
Typical conditions that can occur are mountain wave action and possible vertical winds in the vicinity of thunderstorms. These situations can cause considerable change in indicated-airspeeds. Modern aircraft autopilot thrust controls often hide these conditions so require close pilot attention so a typical pilot may not be aware they are taking place.
In the event of stall at these high altitudes, stall recovery requires immediate release of any aft elevator or autopilot input to allow increasing indicated-airspeed.
It is normal in slower indicated-airspeed flight that the elevator trim is set to maintain a higher angle-of-attack. This requires positive pilot input, pushing the elevator control, to assure reduction of angle-of-attack.
If not attaining immediate stall recovery, delay at the reduced density of very high altitude affects the time and altitude loss required. It may be a minimum loss of fifteen hundred to three thousand feet, and possibly much more, with the related time, possibly minutes, for this change to occur.
An aircraft falling in the stalled condition can only happen with the aircraft manually held in the stall by a confused crewmember. With the acceleration of gravity being thrust equivalent to the gross weight and not allowed to reduce below critical angle-of-attack, the aircraft will quickly accelerate through the rarefied air into a high-velocity stalled descent.
If this happens with reduced power, the ram effect into under-slung engine frontal areas from the increasing mass of lower altitudes can create large nose-down pitch forces.
Recovery may then only occur with added engine thrust to reduce or eliminate the ram effect while simultaneously causing thrust component-lift, pitching up, at the engines.
There will now be that portion of thrust component-lift again contributing to angle-of-attack for a new indicated-airspeed as called for by the elevator position. This procedure requires coordination with nose-down elevator pitch, elevator trim, and increased power.
In all cases, at higher altitudes with the low-density air, this takes time and altitude. Stall incidents with delayed initiation for recovery can take up to twenty or more thousand feet.
