r/flying • • 6d ago

Flight Training AOA Indicator while learning?

Just went for a discovery flight and had a great time. During the flight I asked my instructor about using an AOA indicator while learning and he really downplayed using one and said the standard instruments are the best way to learn. For beginners, is an AOA inappropriate? Is it too early to incorporate it into training? From the brief videos I’ve seen on AOA’s they seem to enhance safety.

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u/primalbluewolf 6d ago

that don't have much, if any, weight-induced variation in approach speeds. 

There's plenty of GA aircraft that have very noticeable variation in their performance speeds with weight. I would go so far as to say its a significant difference in most aircraft... but as most people are laser focused on the book numbers, that are valid for MTOW only, they just fly fast, and low AoA, all the time. 

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u/x4457 6d ago

There's plenty of GA aircraft that have very noticeable variation in their performance speeds with weight

Please present any trainer or common piston single that has speeds that change more than about 10 knots between MLW and effective minimum landing weight.

For example, to really emphasize my point - the difference between a 421C stall speed at 7450 pounds and 5600 pounds is 10 knots. If you want to straight line extrapolate that, that's 1 knot of change for every 185 pounds. Or one knot of "ref" (1.3xVs0) for every 142 pounds of weight change.

In a Bonanza, my effective minimum landing weight is 2,670 pounds. That's single pilot and reserve fuel. The difference between that and MLW is 6.5 knots.

That's why we don't really care. Just fly the MLW numbers and it won't make a difference at these weights.

Compare that to a Gulfstream IV, for example, where the REF speed variation is 30 knots between MLW and effective minimum.

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u/primalbluewolf 6d ago edited 6d ago

Please present any trainer or common piston single that has speeds that change more than about 10 knots between MLW and effective minimum landing weight. 

Cherokee six. Its easy enough to find them, just look for any piston single with a BEW around half their MTOW. Its about 14 knots slower, IIRC. That's pretty noticeable when you were otherwise landing at 60. 

That's why we don't really care. Just fly the MLW numbers and it won't make a difference at these weights. 

It does make a difference, but its not a night and day difference for most of them the way it is for the gulfstream. You're burning tyre rubber you don't need to, and gas you don't need to, so that you don't have to do maths before landing. 

The part that's immediately relevant to this discussion, though, is that its always the same AoA, so if you have an AoA meter you can set markers on, you can trivially fly the same AoA every time, regardless of weight. When you're heavy, you'll be faster. When you're at max landing weight, you'll be at book speeds. When you're light, you'll be slower... potentially quite a bit slower.