In this week’s video and courtesy of the FlightChops YouTube channel, we’re looking at Dan Gyder’s idea for avoiding stalls by simply marking the airspeed indicator with a minimum speed.
Featured Video
AirVenture Video: Alsim Simulator
ALSIM is showcasing the AL250 at AirVenture 2024. Sy Pinkert from AVweb had the chance to test it out and discuss with Jason Da...
Regarding the min speed and computing a speed which is safe, I hark back to my first instructor who taught me that you can stall an airplane at any airspeed but you can’t stall at “0” G. The key being, unload the airplane (fly the airplane). For asymmetric thrust (single eng. failure) He said “don’t hang out anything you don’t till you need it.”
Oops, “don’t hang out anything you don’t need until you need it.”
So let’s see — never go below 1.4 Vs0. Short field takeoffs and landings are typically at 1.2 Vs0, according to several Cessna manuals (if you do the math). Commonly taught final approach speed as 1.3 Vs0. So what he’s saying is no short field takeoffs and landings, and fly final approach too fast. And as for a loss of control accident every few days, not all of them, not nearly all of them, are due to stalls and low speed phenomena. Why on earth did AvWeb think the shallow thinking of this video was worth promulgating?
And what about the concept that a stall can occur at any airspeed, meaning a mark on the airspeed indicator doesn’t guarantee anything and can result in a mistaken assumption of security followed by dangerous maneuvering. I didn’t even hear a connection made to the nose-up trim position at the go-around as being the actual cause of a single-engine airplane pitching into a stall which is learned in trim stall training. Training in trim and accelerated stalls would be more appropriate. Did not like the video.
I think some of the difference presented between what airline pilots said and what GA pilots said is really just a reflection of the difference between the stall behavior of swept-wing jet aircraft versus straight-wing propeller aircraft.
What I said earlier worked for me in J-3s to F-111s( which had no stall recovery) It is not about speed as much as wing loading. At 0 G, lift required is 0, you maybe falling like a cook stove but the airplane hasn’t departed. We used to do a demo in the B757 Sim. Max Gross weight T/O,Max power, pitch to 60 degrees nose up, hold to stall, Push the nose down to 10 degrees above the horizon and leave the power at max. The airplane would recover about 500 feet above the ground. Airspeed can be a bit of a phantasm. If you takeoff in a Bonanza and climb to 50 feet and accelerate to 170 and loose the engine you have little time, if instead you climbed at best climb angle until eng failure and dump the nose to best glide speed you have time.
Wouldn’t Vy be better? For every second/minute the engine ran before failure, the airplane would have gained the most altitude possible.
All the V-speeds vary with airframe loading. Stall speed varies by the square-root of load factor. Bottom line: no single airspeed is universally safe. Part of the problem I have as a CFI doing flight reviews is getting pilots to slow down to proper approach speed and to recognize what actions are likely to lead to a stall in situations where recovery is unlikely.
If you want to discuss instrument readings and markings that will keep you safe we must talk about angle-of-attack and AoA awareness. The only instrument in the aircraft that will always tell you margin from stall is the AoA indicator, something most aircraft don’t have (other than a stall warning indicator).
Personally my experience flying with low time pilots is teaching a minimum airspeed is not likely to reduce low altitude loss of control accidents because I strongly believe all those pilots that lost it while manoevering to land were not looking at the airspeed.
More fundamentally they were not flying the airplane, the airplane was flying them and they were totally oblivious to the fact the aircraft had already entered a UAS with a negative trend. This is because they do not understand and/or can’t apply in real time the basic concept of Attitude + Power equals performance.
My students will near the end of the training do a takeoff, circuit and landing with all instruments covered except for the engine instruments
Finally I think it is grossly unprofessional to deliberately make life difficult for ATC.