Sometimes I am sure this is hot air rising from the tarmac, because it reliably happens on hot days with no wind.
However, I have lately been doing what I consider crappy landings when there was moderate wind, straight down the runway, say 15-20kt. The flare looks fine, and then some tens of metres later the plane lifts off, so I get a hard landing, unless I re-apply power which then results in a long landing roll. The engine is on idle before the flare, usually.
Speed it too high? Or unreliable ASI?
Shallow approach angle with low rate of descent at 50ft, if you enter ground effet on shallow angle without positive (G>1) flare you will float “forever”
In the other hand with -900fpm at 50ft, you bleed that 0.3×VS very quickly !
Hot air sh/could cause the opposite = sudden increase in temperature and density ALT = increase of TAS = increase in V/S sinkrate = hard touchdown if not countered by adding some power?
Otoh you have 15-20kts headwind, lots compared to your approach speed (75ish knots in a TB20?).
My guess is you are simply a notch too fast. Trim and fly the airplane to a speed ~5kts less than usual and see if it works better.
I will second stuff that’s been said above. I’ve helped a couple of pilots fix technique that was causing the same. It’s almost always approach speed too high, and/or the approach angle too shallow. Often these two habits creep in unnecessarily without people realising and sometimes need a little reset.
Shallow approach angle with low rate of descent at 50ft, if you enter ground effect on shallow angle without positive (G>1) flare you will float “forever”
In the other hand with -900fpm at 50ft, you bleed that 0.3×VS very quickly !
@lbra not sure if something was lost in translation? Trying to figure out how any approach shallow or otherwise is anything but 1g? Crashes excepted of course.
RobertL18C wrote:
Trying to figure out how any approach shallow or otherwise is anything but 1g?
The approach is straight line final at 1G of course, it’s the last bit of flare near the ground where thing gets ‘more loaded’ in 7deg approach than 3deg approach due to ‘more curvature’ when flight path changes 
When you positively flare without power from a steeper approach, you load your wings vertically and take some deceleration laterally? that burns any airspeed excess very quickly…I am not talking about 3G loops in glider just from the gentle pull of stick, you would read 1.1Gz and -0.1Gx, that tend to burn some of that 0.3×VS quickly the other way to look at it, is without power at same ASI on high rate of descent you fly on higher AoA and as you flare you get more drag 
I gather it’s the case of lot of short field landings that are done with steep approach angles without power on full flaps, the flare from say 7deg approach to 0deg tend to burn excess of airspeed quicker than similar flare from 3deg approach to 0deg? in addition you spend less time with higher speeds in ground effect
If you stay on 3deg glide path with power on straight line to TDZ like B747 on ILS, please disregard my comments above: VSI is linked to ASI and you are adding lot of energy to the “system”…
PS: you don’t need to cut power at 50ft to land, you can keep it as it is until you vacate but it results in longer float
I don’t understand the above post.
Anyway, I did a landing today in a few kt and it was perfect. It seems to be just in stronger winds. I think the issue is indeed excessive speed, and when one is “pointing down” that excessive speed doesn’t produce much (or any) lift, but when one levels off, the wing is again working like a wing should be, and lifts you off…
Peter wrote:
I don’t understand the above post.
You are doing two approaches in TB20:
- Approach A: 7deg glide path power OFF at 80kts, gear down, full flaps
- Approach B: 3deg glide path power ON at 80kts, gear down, full flaps
Which one results in less float after your flare? why?
Other common issues that people sometimes miss are that idle RPM setting has crept high and when there is some friction / notchiness in elevator causing a bit of inaccurate pitch control in the round out and hold off – a lot of our club machines need a bit of silicon spray from time to time on the yoke control tube
