My guess is that the reason you think a PA28 floats excessively is the you are not arriving at the runway with the correct Vat.
This is a problem I find with a lot of pilots who have been trained in the UK, the training system wants you to add all sorts of increments of speed because they think it adds to safety. The flight manual Vat is demonstrated at MLW so anything below MLW already has a bit of extra speed built into it so you probably don’t need any more speed.
Piper Archer I would be interested to know what your flight manual has to say about the landing distance required at MLW at sea level on an ISA day ?
UK ATOs use the taper wing Worrier for both PPL and CPL. They brief a Vat of 70 knots in the approach, and 60-65 knots for performance landings (UK speak for landing on a short runway), both are consistent with the POH. A performance landing is a required learning objective and is demonstrated in the skill test and on re validations.
In gusting conditions the received wisdom is to add half the gust speed to Vat, so if in this case the gusts were 15-25, 5 knots would be added to Vat.
The reduction in Vat for lower weights, say 1900 lbs, not the case in this incident, would reduce Vat by around 5 knots using the square root of the proportion of actual to MLW rule.
As the Worrier is ubiquitous round the world I am sure these SOPs apply universally.
Robert 18C
In theory you are correct but that is not what I see in reality, I get to fly with a lot of PPL holders who need to do the bi-annual flight with an instructor and you would be amazed at the reasons for adding incriments to the approach speed but it all adds up to the aircraft floating half way down the runway.
I have now given up just giving these guys a quick brief and then going flying, an hour in the classroom looking at aircraft performance is usually an eye opener for them and the subsequent practical application of that knowlage always provokes an interesting reaction.
Next time you are in the flying club bar ask a few people what RPM setting they use for 75% power or what Vat is ? The answers you get will be revealing !
QuotePiper Archer I would be interested to know what your flight manual has to say about the landing distance required at MLW at sea level on an ISA day ?,
I need to check that, I am away in Germany at the moment so no access to my POH at home.
My guess is that the reason you think a PA28 floats excessively is the you are not arriving at the runway with the correct Vat
There is probably some truth in that, but when I changed many years ago from the PA28-140 to the -181, just the differnt wing design tends to give a more floating / ground effect than the -140, or even a Cessna 150 type machine.
This is a problem I find with a lot of pilots who have been trained in the UK, the training system wants you to add all sorts of increments of speed because they think it adds to safety.
I don’t think it’s necessarily “the system”. I got checked out at Barton in a C172 a few years ago and you can bet the instructor wanted me to come over the fence at the proper (not fast, no silly increments) airspeed, and slightly slower than the book speed because the book speed was for at gross weight and we were only two light people with half fuel. However, a friend of mine was getting checked out to fly at the now defunct Ravenair operation at EGNS, and the instructor really didn’t like him to go below 70 knots(!!!) on short final in a C172 (the book value for a normal landing at gross weight is 65kts, IIRC). We so wanted to take that instructor flying in the Auster where you can make a wheel landing out of a 40 mph approach.
Alioth
It is a problem with the system simply because it is not weeding out the people who are not doing the instructing job properly, most of the trouble comes from people who aspire to flying a jet airliner and have seen too many in cockpit videos.
There is a lot of “SOP” at flying schools some instructors are forced to use…
Here is a little anecdote. I got my instructor rating on a PA28, simply because I did not fancy my CFI enough to want to rub shoulders in a C152 for 40 hours – although he is a lovely gentleman.
But of course I had to teach in a C152 as well, so I quickly enquired the speeds we teach (“everything is 65 kt”) and went into the circuit. Boy, did I struggle with the landings…
So after 3 landings I returned, read the performance section in the POH, went back up, flew 10-15 kt slower, and everything was beautiful…
After an “interesting” conversation with the CFI (who, slight disagreements not withstanding, I rate highly!), I went back up again, and learned to do it at 65kt.
“what shade of blue, sir?” ;-)
One thing that strikes me: this incident is discussed at length on every aviation forum I frequent, but I have yet to see the METAR ( s ) .
(I could search for them, but I am sure some here know how to find them in 1-2-3)
What was the actual wind at the time?
but I have yet to see the METAR ( s ) .
EDXH does not release METARS! They have an automated weather display on their homepage (http://www.flughafen-helgoland.de/informationen-fuer-selbstflieger-nach-helgoland-edxh.html) which might or might not have an archive, but that is probably not available to the public.
That’s a good explanation. Still, I find it hard to imagine there would not be a weather station at this unique location that doesn’t keep logs – the question is indeed who can read them. At worst, we will have to wait for the official investigation report – if there ever comes one. Perhaps not, as there were no (physical) injuries and material damage was very limited.
