Greaser Landings

[MJP]

:confused:

I'm a trainee flight instructor and I need some sound advice from some more experienced folk out there, about what to teach my future students.

When I did my CPL at a military flying club, I was taught that a "good landing" meant touching down at or near a selected point - a firm/positive , but not hard landing, was graded as a "good landing". Maintaining the correct profile and consistency were emphasised over the "smoothness" of the touchdown .

As an aspiring flight instructor, what should I highlight with my future students?

[The Stooge]

Greasers is not what it is all about as you said a stable approach is what you are looking for. Constant profile ie 3 to 1, constant attitude and power. Remember power + attitude = performance. No other way to fly an aircraft and as for power = rate of decent that is bull sh!t. Every one will argue for it and against it but tell me how do you fly an ILS? the aircraft doesnt know any different as to if it is on the ILS or not. As said what you are looking for is a constant aiming point and maintaining desired speed (correct Vref) from about 400 ft, if you are too fast you will float and use a lot of runway which can be valuable for stopping. Positive touch down is what you are looking for not crashing it down but positive. Let me tell you airlines take a dim view to trying to squeak it on because that says one of a few things and the major ones are you are not flying the correct Vref or Vfa for the weight and the bigger the a/c a few knots means a lot of momentum and you will generally have to use a lot of reverse and breaking which is not good for pax comfort and not to mention airframe/engine stress. Dont get me wrong if you need to use breaks/reverse USE IT. If landing on a wet runway you will always wnat a positive touchdown as 9 out of 10 times your touchdown speed will always equal your aquaplaining speed(Sq root of tyre pressure X 9). And otherwise a good landing comes from a good approach and good techniques and as a flight instructor that it what you have to be able to impart to your students. But first of all you have to have the process under controll as there is no point in teaching someone and you are finding it difficult yourself as that will promote no credibility. Otherwise work hard at it and over time the techniques will come to you. Not every landing will be a good one but as long as you employ the correct techniques every time. Good luck and I hope this has been of some help. :ok:

[MJP]

Stooge,

Thanks mate, for you helpful advice. I was feeling a bit like a pariah and heretic around the local aeroclub. The reasoning given by my colleagues for aiming for smooth landings was the inherent "weakness" of the average light aircraft undercarriage(?!).

I've used the "power & point" technique leading to a "positive" touchdown on ultralights (ie LSA 55 3/J "Jabiru") and it works well!
I've flow with ex-mil / airline qualified friends who emphasised safe and professionally-executed landings resulting from using the correct profile techniques - a "greaser" is a nice-to-have.

I cringe a bit when I watch C-172s / PA-28s leaving a trickle of power from hold-off to touchdown to get a smooth landing half-way down a 1374 metre runway, at a local Air Force airfield. I'm thinking: "that can't be right!?" Thanks again.

Aye,

MJP


:ok: :ok: :ok:

[The Stooge]

Well year some aircraft you have to leave a tad of power on in the landing but certainly not in a PA28 or C172. Some big singles you have to like a PA32 as when you close the throttle the aircraft conciders flying over, like the aircraft I fly there are two models and one has a bit less power than the other and in the lesser powered model when you bring the throttle to flight idle the props are basically in ground fine and flying will cease and especially when we start to flare at about 50 ft or so that can lead to a big crunch. You tipically need about 20% power to help pull through the flare and some small twins are like thet like the C310 and so on. But it is all just a matter of flying the drag curve and closing the throttle at the right time.

[MJP]

I think your last sentence says it all really - when to close the throttle.

I find that the "low inertia" of the LSA 55 Jabiru makes it want to cease flying after the throttle is brought to IDLE maintaining Vref to the flare /round out; just like a PA32. So you end up with a positive touchdown. Some of my colleagues will leave a trickle of power in the Jabiru to get a greaser, which I guess is OK for them. I've seen others do a botch job when a sudden gust and that trickle of power ballooned the aircraft, into a semi-stalled drifting situation with ineffective flight controls.

Read an article called Great landings vs. Soft Touchdowns in P-3s in the U.S. Navy's [COLOR=darkblue]Approach (May '82) Magazine which made me think about what constituted a "good landing".
New P-3 pilots joining a squadron suffer a rude awakening when landing on the mains; at the proper speed; at a specific point and on centreline with a slightly firm touchdowm is not considered a "good landing".

To avoid ridicule, the P-3 pilots learns that he can make consistently soft landings by landing flat; at midfield with power on to keep the crew happy!!!! What happens when there's snow, ice, water on the runway the author asks.

I wish I could share the last paragraph of that article with my mates. I reckon the principles provide sound advice. I quote:-
It is a true confidence builder when a pilot can make a landing nose high; on centreline; in the first 1 000 feet of the runway, with zero thrust at touchdown. When he can combine a "great" landing with a soft touchdown, the multi-engine pilot will experience a feeling so good it's almost indecent. And do you know what the best part of it is? It'll be a SAFE LNADING with PROPER PROFILE TECHNIQUE.