Throttle technique during landing

[Pilot DAR]

Since excess height is a lot easier to spot than excess speed, isn't this the biggest argument for nailing the POH approach speed from the top of final approach?

Sounds reasonable to me... Nailing everything is the best though....

If you're too high, you can slip the speed off, should you choose that technique. Otherwise, you're going to have to add drag somehow, or speed up. Though not a physics expert it seems simple, whatever you carry in excess over the end of the runway, you'll have to get rid of, to come to a stop. Other than a change in configuration, that will translate directly into runway length used.

Personally, I am more likely to fly an approach in an unfamiliar aircraft or into a tight spot, which much more "eyes out" and by feel, rather than watching the airspeed indication. Once setup in configuration, and on speed, I will generally fly the rest by feel, only looking back at speed if I have a concern.

I recall landing a Grand Caravan into my home runway last summer, in probably my third or fourth landing ever in a Caravan. My home runway is short and quite narrow for a Caravan, so I was really paying attention. My check pilot was too. After a respectable landing with adequate room all the way 'round, I looked over at my check pilot, who seemd a little rattled. "Nice landing" she said. "Thanks!". Then she said, but I was having trouble figuring out how you flew the approach at 50 knots...". "Huh?!" I replied. I realized that I had been flying by feel, and had no idea what my speed was crossing the fence, it just felt right. Then she told me she had looked over at my airspeed indicator late in the approach, and mine was indicating 25 knots more than hers, so she decided not to say anything. We confirmed after more flying that the right side ASI was way out, later found to be a pitot line leak.

By the way, for the sake of the original question, the Caravan is set up with some amount of braking ("beta", but let's not call it reverse) pitch setting at idle, so they really do come down power off. You can certainly land them quite nicely that way, but speed bleeds off quickly. It has the effect of tempting pilots to carry a bit of power mid approach, which is a good thing in a turbine, 'cause they take a little longer to spool up from idle, if you need a burst of power. It's part of the type familiarization to know that once (or if) to reduce the throttle to idle in the flare, it's going to slow down faster than many types. When gliding a Caravan at idle power, feathering the prop reduces the sink rate considerably (and feels like a good shove from behind).

[A37575]

the optimum short field technique requires power to be on until the aircraft is in the landing attitude and near the ground - when it's removed the aircraft promptly lands.

This is true if you have reduced the final approach speed to barely above the stall with the stall warning sounding. This was a wartime technique for landing into unknown length strips. Of course there was no stall warning horn although in a Tiger Moth the slats would flutter in and out and were a reliable stall warning. Nowadays we would call it a minimum ground roll landing - which after all is why the former short field landing or precautionary landing was all about in the first place.

But where light aircraft flight manuals landing distance are usually predicated on a min speed of 1.3 VS at 50 feet with power off, the true short landing technique (1.05 VS) is a thing of the past. One often reads of flying instructors talking about using the correct 1.3Vs landing speed as a short landing and then brief the effect as if it is on the point of stall and no float. That is incorrect. However, because most instructors teach their students to approach somewhat faster than is needed (presumably to allow for error and give a longer float for smoother touch down), then the faster approach is considered a `normal` approach - while approaching at the flight manual recommended speed is seen as a `short field` landing and to be undertaken with extreme care...

Interesting that jet airliners cross the fence at the flight manual recommended speed for a normal landing. There may be wind component additives but nothing extra thrown in for mum and the kids. But Cessna would call it a short field landing...

By definition, today's short field landings are flown at the same speeds as normal landings even though the Cessna Manufacturer's Information Manuals label their landing distance charts "Short field".

Confusing I know but it helps to know one's history.

P.S. Extract from RAF Pilot's Notes for Chipmunk. AP 4308A - PN Date 1950. Part 2 sub-para 30. Approach and Landing:
"It is recommended for all conditions that the airfield boundary be crossed at a speed of 55-60 knots. The initial glide or powered approach should be made at 60 knots.
For a precautionary landing an initial approach with full flap under power at 55 knots is recommended, aiming to cross the airfield boundary at about 50 knots". Unquote.

Stalling speed under typical approach conditions, flaps fully down is 35 knots. That applies whether power is on or off.