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View Full Version : Max performance T.O/Steep approach from one side of an airfield to the other


stevenwings
8th Jan 2011, 04:11
I'm currently training students in the R22 and have been doing a max performance take off from one side of the airport, leveling out at 250 feet and then doing a steep approach to the other side. The control tower has no problem with me doing this. After the steep approach we then do another max performance t.o and fly the patten. This allows me to make 2 approaches/takeoff's in the one pattern. Although I am outside of the H.V diagram, do you think this unconventional pattern is a bad idea to practice with students?

JimL
8th Jan 2011, 07:42
Are you outside of the HV diagram?

Jim

Bertie Thruster
8th Jan 2011, 07:55
Do you feel outside of your own HV 'internal algorythm' or are you happy at all points?

HV 'internal algorythm'= 'if the engine stops now, I've got the feeling we will probably die.'

If not.....carry on!

ReverseFlight
8th Jan 2011, 09:38
As it were, the HV curve subscribes the "avoid" area. While not prohibited by the POH, you venture at your own risk.

stevenwings
8th Jan 2011, 10:39
Apologies, I should have been a little more specific when stating outside of the H.V curve, I was referring to when leveled out at 250 feet/airspeed 50 knots. I should also point out that the airfield elevation is sea level and we're approx 80 pounds under max gross weight. Obviously during the Max T.O/Steep approach I would be inside H.V curve but I was of the understanding that this is always going to be case when doing a Max T.O/Steep approach.

Thanks for the replies so far.

topendtorque
8th Jan 2011, 11:57
I was wondering whether it was a question, or a statement? but I think I've worked it out.

It's the best place to teach them, because if the engine quits the crash truck'll be right there. Unless it's gone with the budget cuts.:{

The engine won't quit you say, ah ha that's what they all say := :ok:

Your students always check keys t's and p's before lift off, do they?

Of course not, they're the kind that will wander into the hangar with tail boom across the shoulder and some cock and bull story about a magneto failure during a confined area take off.

Well, just let them get to about six feet and go back to one mag. that with a few sharp words and a clout if necessary should cure them. It wasn't the mag failure that old mate crashed with, it was his stupidy to not check the damm things. Naturally you have by now also taught them how to handle an aborted T/O due to partial power failure. easy eh? two lessons in one.

And you are right, when operational and in a real confined area its always a matter of proper control, letting down slowly so's you can always go round before committing, just pretend the HV curve doesn't exist because in real life there is no choice due to trees etc. you'll hurt anyway if the thing stops, get over it and just do them as you feel the student would in the bush. save us some time. yeah, but do some landings amongst trees before you finish with him.
cheers tet

JimEli
9th Jan 2011, 00:59
The HV diagram was defined via specific parameters/techniques above/below the knee point. Don’t simply fear it, but rather understand and respect it.

stevenwings
9th Jan 2011, 01:30
Yes tet, we check keys, t & p's and do the standard b4 t.o chx, including the clearing turn. Judging by the responses so far, looks like it would be a good idea to stop doing this kind of pattern. However, perhaps we should also consider that the H.V curve is designed for T.O/O.G.E hover not for the approach and straight and level portion, although I believe it is still important to extrapolate as best we can the info from the H.V curve to the low level s & l segment and approach as obviously the closer to the H.V curve we are, the less time we have to lower the collective to maintain rotor r.p.m to make a safe auto in the event of an engine failure.

Although I am looking to do things in the most efficient way possible, I’m not looking to compromise safety, so welcome further critique sarcastic or otherwise.

chutedragger
9th Jan 2011, 02:16
Good topic! My opinion is based on watching guys rock down the infield in a jet ranger at 10 to 15 feet until 50 knots (indiacated airspeed wich we know is a little questionable on a nose down pitot tube) and then climb out. "All in the name of the height velocity curve". I say to that...with my thousands of hours, I dont kid myself to think that I am that good, that when the engine quits at 50 knots and 15 feet of elevation that I will have the reflexes and skill to get my S**t together before I pile into the ground making a BIG jet ranger fire ball...or flare and put the tail into the ground.

To me...the bottom end of the HV curve is for the 100% safety of the aircraft!! (ie. training) thus obviously the occupants are 100% ok too! To me (have seen a friend die in a jetranger fire ball) I would rather climb out on a nice steady 30 to 40 knot airspeed through 50 - 75 feet profile. I know it will be a hard landing, and collapse the gear ect. , but me and my pax should be ok. Rather limp, than burn.

Just my thoughts and the way I like to fly. It also doesn't look cowboy, with a nice gentle depature.

Not saying I am right...comments either way are open. Like I said, a really good topic. Lots of this discussion around the hangar.

hands_on123
9th Jan 2011, 08:18
If you are pre-solo with this student then its an odd way to teach them to fly circuits.

Remember, solo students will do whatever they have been taught to do. You don't want solo students doing max perf takeoffs all over the place.

Much better to teach them a normal takeoff/transition and a normal approach?

VeeAny
9th Jan 2011, 09:07
Although I am looking to do things in the most efficient way possible, I’m not looking to compromise safety, so welcome further critique sarcastic or otherwise.


In that case stop it !

First of all I agree the risk of engine failure is small, however in two years time when one of your students takes you to court because this is the way he flies and he hurts himself when his aircraft suffers a mechanical failure (or he has a mag problem, or encounters Carb Ice), you are in a precarious position.

I am assuming you are teaching JAA syllabus in the UK based on your location.

Would your FIE be happy to chop the throttle on you at any point in your pattern in an R22 and let you land it ? I would suggest not.

The H/V curve should not be feared it is (as has been done to death on PPrune before) constructed for take off and tested in level flight (for this category of helicopter). However it sounds like you are taking an unnecessary risk with a student, who is most likely not capable (through no fault of his own, he is early in his course) of knowing just what that risk is.

Later in the course when he needs to perform manoeuvres like this and has had the risks spelt out to him as part of his pre flight briefing, it is perhaps more acceptable (but no less interesting if there was a mechanical failure while practising it).

Is the 'Max Performance Take Off' in the JAA Syllabus ?

I would suggest the consequences of a mechanical failure (not the likelihood of having one) are much worse in an R22 in this scenario than in any other certified helicopter.

There are a whole host of problems which might end up with having no torque (engine or drive belt failure), or needing to get rid of it (tail rotor, or drive shaft failure) at such low altitude and airspeed that, whilst it most likely possible for some pilots to walk away without a scratch from these situations, most average pilots will not, I would contend that because you are an instructor does not make you (or any of us) above average (you might be, but I am generalising).

I know people operate in this area every day without problem , my issue is with doing it at such a stage in the pilots training as to be unnecessarily risky when it does not need to be.

If (one the rare occasions) I do any training that requires a vertical climb out of a site in a single engined helicopter (single tail rotor), I accept the risk as does the student, we both know what the consequences are of a failure and fly defensively, that does not mean it won't hurt if all hell breaks loose.

Gary

Paddyviking
9th Jan 2011, 09:13
Remember quality is better than quantity, better to get a few correct circuits in rather than a few rushed ones
The student will copy what you do (or try to)
As others have previously stated, fly safely and the student will fly safely
if you deviate from normal practice so will he :=
Will you feel confident letting him do what you do ---- solo ??
If he/she prangs the heli while trying to repeat what you've shown him
how would you feel then
just speaking from my experiences :ok:

regards
Pv

Torquetalk
10th Jan 2011, 21:03
Agree with previous posts: teach what your student can understand and put into practice. Your student will copy you. That Max Perf departure is fun... the steep approach too. But why do we do them and when? And where do they belong in the training syllabus?

Students who seem a bit nervous when doing a vertical climb, over trees with one engine, worry me less than those who don't bat an eyelid.

Hughes500
11th Jan 2011, 08:29
Cant see the point in doing as described ? Remember students are very impressionable when learning to fly and will try and copy what you do. There is a particular reason why we acclerate an aircraft to 40 ish knots and climb away.Most engines will misbehave when under full power, if you dont need full power dont use it, if you dont need to do a vertical take off dont do it. Always teach your student " what if". Yes you do need to teach max power take offs out of confined areas the same with landing, but this should be drummed in as the exception rather than the rule. Having had an engine fail in the avoid curve I can assure you it is not nice and concentrates the mind like nothing else.:ok:

500e
11th Jan 2011, 09:49
Never liked the brow trim in that 300 anyway H 500