mary meagher

Backpacker, could you explain what a safety altitude at 50 meters involves? safe for what? the 150 meter abbreviated circuit call, would that be 450 feet? not a lot. If this is a mantra recited before every launch, it will not require any thought or planning. I feel that rigid drill of this sort does not take into consideration the variety of airfields we use. At Lasham, for instance, any cable break is a land ahead, because the field is so big....and it really should be the FIRST CHOICE! If you are programmed to do an abbreviated circuit from 450 feet, is this best practice?
Seems to me that each gliding site will have particular assets and limitations, and the student should explain carefully, before flight, his plan in the event of a launch failure. On a strong headwind day, you can land ahead from almost any height. On a very light wind day, or cross wind, or whatever, the student must be able to adapt and plan for conditions.

Back in the days we winched with piano wire, we were pleased to get a launch to the top without failure, it was a common event. I pulled too hard one time, broke the wire at about 700 feet, which came down like spaghetti all over the winch, and decided to spend the next couple of hours soaring.....anything but return to face the music!

Pilot DAR

Mary, what type of music is produced by a tow winch covered in piano wire?

BackPacker

Mary, we were taught to use a rather shallow climb attitude (30-45 degrees or so) for the first 50 meter because with a steep nose up attitude you will not be able to recover from a cable break fast enough. After 50 meter you can pull to a very steep nose up.

In reality it's a rather smoother process where initially you let the aircraft accellerate until 130 km/hr or so, and above 50 meter you smoothly pull a bit more, for a target speed of 100-110 km/hr.

Last instructor I had did not bother with it that safety altitude at all, as long as you did not climb too steep initially. He told me I must've been taught by an old school instructor.

chrisN

BackPacker, you might like to look at the BGA guidance in “Safe Winch Launching” Feb 2010 edition and other stuff on:


British Gliding Association >> Safety >> Safe Winch Launching .

Note particularly: “Ensure that the transition from level flight at take off to the full climb (typically 35º) is controlled, progressive, and lasts at least 5 seconds.”

(The safety initiative of which this is part has succeeded in reducing UK winch launch accidents by a huge percentage.)

Chris N.

ChrisVJ

I have real concerns even discussing the "Turn back option."

I have no doubt that a well trained, well practiced pilot can, in some circumstances, turn back for an EFATO. However I also take on board the traps, practice is not the real thing, manoevres close to the ground may seem different to practice at safe height etc.

All three people I have known personally lost to GA aviation accidents were lost to stall/spin at low level and one of them, an experienced guy flying his own plane was an EFATO attempted turn back.

My first instructor was adamant. For EFATO land straght ahead, ploughed field, trees etc, land straight ahead.

In general I approve of all sorts of discussion on Pprune, however this discussion seems full of danger. There may be those who see the discussion and come to consider turning back as a legitimate option 'on the day' though it is either beyond them, beyond their aircraft or beyond their circumstances, even taking the time to think about it may cause unacceptable consequences.

Once upon a time the world was a simpler place. Instructions were clear and we all accepted them. Nowadays it seems there is always someone who promotes another idea and usually thats OK, but for this discussion I have serious reservations.

However that's just my opinion.

BackPacker

ChrisN, thanks. The advice in there is consistent with what I've been told.

oscarisapc

I too have real doubts about the wisdom of practising turns back after EFATO or of promulgating what an ace pilot has achieved in practice. I am not a hot shot pilot and in the heat of the moment reckon I would be so unnerved by a failure for real that an ability to fly accurately on the edge of the stall would be non existent. Flying at the edge of the stall is not normally the best glide speed and things are going to be worse anyway with the engine stopped for real as opposed to idle. I have practised180 degree turns after a simulated engine failure in the climbing attitude (but at a safe height, not at ground level and using a straight road as a reference) and found I couldn't get round in less than 600 to 700 feet and that didn't allow for the additional S-turn needed to get back on the centre line. The other thing I noticed was that in my plane it takes some time and horizontal distance to get to 700 feet so that even if a turn back was possible vertically, it might well not be possible horizontally and you could fail to reach the runway if it was short. Much better to face the inevitability of an into wind forced landing than a wind behind you forced landing into the airport threshold. And if you know that "EFATO = Lower the nose and Land ahead", you can plan for that as an instinctive drill, so that when the moment happens you don't waste time whilst your brain unfreezes.

Thanks Mary for your comments on cable breaks - I am just about to try my hand at gliding so it is interesting to realise the same issues occur,.

Genghis the Engineer

I read what the naysayers above say, and can see where they're coming from.

However, I doubt that many PPLs (particularly those who like thinking hard about their flying, which is probably most on PPrune) will simply launch into a turnback into an emergency, when they've been trained to land "ahead". Not on the basis of what's been posted here.

On the other hand, it's already been demonstrated that some pilots as a result of reading this will go up to a safe altitude, and try flying a simulated turnback manoeuvre to understand and rehearse how it would work,and whether it's a good or stupid idea for them, flying their own aeroplane.

I cannot see any harm in that.

G

oscarisapc

ThesaurusLegend: Synonyms Related Words Antonyms
Noun1.naysayer - someone with an aggressively negative attitudeobstructer, obstructionist, obstructor, resister, thwarter - someone who systematically obstructs some action that others want to take
technophobe - a person who dislikes or avoids new technology
Based on WordNet 3.0, Farlex clipart collection. © 2003-2011 Princeton University, Farlex Inc.

I don't see that folk who are stating "Don't even think about turning back" are naysayers. An awful lot of good, experienced pilots have been caught out by the impossible turn thinking they can just beat it and this recurs every year in the Accident Reports.

Genghis the Engineer

I think some people have been aggressively arguing against attempting turnbacks. So, without denegrating them at-all, they are naysaying, with reasonable grounds.

I can't help feel that in most cases a pilot attempting an unpracticed and untrained manoeuvre, may be experienced, they are not "good".

G

The500man

I think it's worth putting effort into working out how to make a successful turnback for the times when there is no other reasonable option (particularly if you fly from that type of runway regularly) but if you had a suitable landing site ahead or even to one side why would you turnback?

If the only option was to ditch, would you consider that better than attempting a turnback if you had what you considered to be sufficient altitude for a turnback based on prior practice at altitude?

Out of interest do people that would turnback think they would still have enough spare capacity to make a mayday call? Landing with a tailwind could mean using a lot of runway, and someone else could well have already lined up behind you. Obviously you would have to rely on fast reactions from non-radio aircraft on the ground or on short final.

When you really think about it, is it worth the effort training yourself to turnback? Unless you do fly from a no-other-option-airfield regularly what are the chances you will have an efato somewhere that actually requires a turnback?

BackPacker

My personal objective in participating in this discussion, and possibly in future trials as well, is to better understand the mechanics of the maneuver, to get a better understanding of the factors involved, and to get a better qualification of turnback height.

Right now, depending on who you talk to, the "no turnback" height is somewhere between 500' and 1000', without further qualification or any consideration for aircraft performance (MTOW or not), circumstances (Wind, altitude, temperature), runway length/layout or anything.

I know there are aircraft that will not be able to make a successful turnback from 1000' (a fully loaded DA40-TDI for instance), and likewise there may be aircraft that can be turned back at less than 500' in the right circumstances.

If, at the end of this exercise, we end up with a series of graphs, guidelines or something else, that allows you to calculate a realistic turnback height (including a safety margin, and which takes into account reaction times and assumes only moderate pilot technique) for your specific aircraft and circumstances, then I think we've done a good job.

But obviously below that calculated turnback height you can't turn back and still have to land ahead. It's only above that height where you are given the option to turn back, or to land ahead. And "land ahead" might then still be a better option.

Tough question, but probably more or less comparable to the question of whether it's worth the effort of training yourself to do, for instance, short/soft field take-offs and landings.

If you always take off from hard and long runways, maintaining soft/short field skills may not be all that important. And likewise, if you always take off from airfields that offer plenty of land-ahead options, it may not be important to acquire the turnback skills that the eventual procedure may demand.

'India-Mike

Of course the outcome of Genghis' research might be "don't do it". Research is there to derive negative answers too, and in this case the outcome is not necessarily a toolkit to allow pilots to do it.

Personally I'm not a fan of turnbacks, as a pilot or FI. I'm not really worried about aggressive manoeuvring at low level. It's kinetic energy that bothers me...I'd rather contact the ground without a tailwind. Even a few knots in a SEP is noticeable and can require its own skills, especially tailwheel. I suspect an off-aerodrome crosswind forced landing might produce a better outcome for most pilots than a turnback.

But that's research and without it all is supposition.

Genghis the Engineer

That makes a further thought occur to me - ability to land downwind at-all in any given aeroplane should probably be a further aspect of the research question, and downwind landing performance.

Just envisaging *possible* research outcomes they might come out with a series of "success" bands:

Red - You won't succeed
Amber - You'll get it on the runway but almost certainly go through the hedge
Green - You have a good chance of success.

Possibly defined by a combination of aircraft performance, runway length, and wind.

(Or not, I am conjecting - "it's a damned fool idea under most circumstances" is also a valid research outcome, even if I'd not word it quite like that in a paper for Aeronautical Journal.)

G

foxmoth

Ploughed field - OK, trees, maybe, industrial estate - could be OK, but depends on roads, empty car parks etc, same with built up areas - 3:45 as the kids are all arriving home, maybe not such a great idea, same with ditching - calm summers day with loads of boats in sight, maybe OK, rough winters day, maybe not.
There are not many places I would advise a turnback, but if you are flying from one of the few with no realistic options, IMHO it is good to know what you and your aircraft will do - turnback does NOT need to be to the runway by the way - 120 degrees or so might get you to decent fields, but whatever your options, they need preplanning and thinking out ahead of the T.O., and having practised at height you will at least have SOME idea how to go about it without spinning in.

peterh337

I don't know why so many people are so clear cut about a turnback being a BAD IDEA always.

I recall one departure from Antwerp. It is "only" 1510m, but I was at nearly 1000ft by the time I crossed the end of the runway (it was quite windy).

I think that the biggest risk in a turnback under those conditions would be to overshoot the whole airport

So much depends...

The500man

If on the climb-out your engine quits, you would push the nose down and maintain best glide, but aside from that would you attempt a restart? It's fairly quick to select a landing site in your field of view and then move on to a memorised restart drill, and then make a radio call, and then go through a memorised shut down drill before concentrating on actually landing. If you are going to turnback and you make the decision before-hand, surely there isn't the time to do anything other than turnback immediately and forget everything else. If the engine was actually on fire, you'd want to complete the shut down checklist, even if turning back wouldn't you? What about feathering the prop? I wonder how much altitude would be lost while undertaking these tasks.

It would be great if a standard procedure could be developed to give pilots a rough idea on the chances of a successful turnback, and I agree "success" bands would be a very good way to relay that information.

n5296s

Couldn't have said it better myself. That was certainly MY motivation for understanding this manouevre better and seeing how it works in practice.

As for the "not in front of the children" mindset... where do you stop? What about aerobatics - a frequent source of fatalities among people who decide to try it without instruction or the right aircraft. So should we ban all talk of aerobatics just in case some 50 hour PPL decides to take their PA28 and try to fly a Lomcevak?

This particular thread says "don't try this, don't do this" every third post. That said, there are those of us on here who - while certainly not being "hotshot pilots" (not me anyway) - have enough experience and curiosity to want to know what would happen if this really was the only option, or at least the best one.

You could apply the same thinking to spin training. Arguably many of these sad cases of stall/spin accidents wouldn't happen if people had flown a few spins and weren't thrown into complete panic the first time it happens to them. (Personally I'm a huge advocate of requiring spin training prior to a pilot's first BFR or equivalent). Yet it doesn't happen because it's "too dangerous" (and I probably shouldn't be talking about it in front of the children, whoever they may be).

At the end of the day it's only flying. The airframe doesn't know you're at 200 AGL. And you can always practice at altitude - should in fact, if you're going to do anything. Only when you're VERY comfortable with hairy-edge-of-stall-in-steep-bank flying with a few thousand feet of air under you should you even contemplate doing it closer to the ground.

Crash one

Well, I've read the whole thread, very interesting. There is obviously no definitive height that can be applied to all situations/aircraft. To my way of thinking this amounts to how much height is lost for a given radius of turn with no power, in my aircraft, without "losing it". The other thing I would try is how much height do I need for a "circuit" to land into wind. Now, the next thing is, when I do this exercise at the safe altitude of 2000ft+ & wx permitting, I will not under any circumstances hold any of you responsible for whatever outcome. The aircraft is a Piel Emeraude CP301-A, 90hp Continental. It stalls at 40kn with a heavy passenger (ATPL training Captain) just to keep the Nanny state at bay. I have 210hrs total, 120 on type. So perhaps that puts me in the low hours killing zone category, I am 72yrs old in a few days & intend to raise that figure by a factor of 1.3 at least. I suppose I should also say that the strip I fly from has numerous options for land ahead on both ends of the runway, so I am unlikely to need this option.
Whoever said that this "training" is unnecessary unless you might need it is wrong in my opinion, there is always a use for training/practice in whatever form.
The purpose of such an exercise for myself would be to enhance my knowledge of my aircraft's performance as well as mine at the edge of our envelopes, I do not have a POH.
It seems a pity that discussions such as this brings out such a lot of "Don't do this at home" advice. Perhaps this sort of thing should be taught at PPL "close throttle, perform 360 deg turn with height loss of no more than xft", preferably with stall warner blaring, if you have one.
n5296s
I think you are hitting all the nails on the head, keep it up..

mm_flynn

This is quite true, however, a 200 foot error at 200 AGL will be far more noticeable to the airframe than the same error at 1000 AGL!

I am not that convinced on the 'impossible' land ahead options having flown out of just about every one of the fields mentioned. Places like Bembridge or Oban I have always assumed an engine failure at 200 feet would be a ditching - but close to shore and with a very high survival potential. For many of the other fields , there are reasonable patches that a no gear aircraft can slide to a stop within (after all, the gear is almost surely on its way up at this point - Murphy after all ).

A lot of this conversation is aircraft and environment specific. Full up, my Bonanza climbs slo o o w l y and on a straight out departure there is no turn back altitude from a short field (unless I am taking off into a gale), hence I prefer an early turnout which keeps me within range of the field (and with 90 degrees of the turn already done).


I would definitely encourage trying the manoeuvres. I was surprised at how nicely my plane pitches into best glide if I just 'let go' during an engine failure simulation (assuming I have set proper takeoff pitch). Equally, I tried flying turnbacks with a pretty good model of my aircraft in X-Plane and found hitting the runway was very hard, hitting the field from crosswind was pretty easy. Doing the theoretical turn at altitude was quite a bit easier than getting back after the randomly timed failures in the simulation.

Finally, as noted by others, I was also very surprised at how much of an improvement in glide ratio was achieved by going full corse on the prop.