THE MAIN DANGERS OF BIG EARS

More on this manoeuvre which we all thought was as safe as houses
From Cross Country magazine, June 1998



There have been a couple of incidents recently involving pilots using Big Ears on landing approach only to find themselves dumped in and needing hospital attention. The FSC is obviously concerned and is also aware of the article (Bruce Goldsmith) wrote in 96 for Cross Country. We are in the process of gathering info on the subject in order that an informed statement be made on the use of Big Ears.

The problem is that the average pilot now has it in his head that big ears is a good, safe way to top land in strong/windy conditions also, many Brits are using the technique to land in thermic Alpine landing fields. Their reasoning behind this is that, with the ears pulled in, the wing loading must be increased, therefore the wing must be more stable.

In reality the situation is far more complex with potential changes of angle of attack and stall speeds (especially when pumping the ears out), etc.

Dave Thompson
BHPA Technical Officer

Bruce Goldsmith replies:

It is most important that the flying public be educated into the dangers of Big Ears. This is an emergency manouvre and should only be used as such. This is becasue Big Ears itself has several dangers and should not be done as a matter of course. The more circulation the subject gets, the better. I have just been discussing this problem with André Rose of ACPUL and Peter Brinkeby Airwave test pilot and the synopsis of our discussion outlined the main dangers of big ears:

1) Deep Stall on Release of Big Ears

I personally know of two broken backs due to this. The problem comes from when the pilot tries to pump out the big ears. the glider is already descending more vertically than normal, and when the pump is made on the brakes, the angle of attack increases even more and it is easy for the glider to enter deep stall. It is safer for the pilot to actually land with the big ears still in!

2) Front Collapse in Big Ears

If you do Big Ears and then get a front collapse you are in real trouble.

You cannot 'active pilot' to avoid the collapse in the first place because the brakes don't work properly, and the glider is folded up so much that it will take twice as long to come out. Nobody even tests this manouvre, so don't be the first one to try it when only 10m from the ground.

3) Reduced Manouvreability

A glider in big ears is less manouvreable because the brakes do not work properly, and you cannot active pilot to avoid collapses. No top level pilots use big ears on approach because it is more dangerous.

4) Dumping in Wind Gradient

If you use big ears on approach and there is a strong wind gradient you are more likely to be dumped into the ground when the glider lacks airspeed and is not fully inflated.

Bruce Goldsmith.

(From QA (Questions and Answers) in Cross Country No. 57, June 1998)


FURTHER OBSERVATIONS AND QUESTIONS ON BIG EARS

It is with great interest that I have read the QA article in which the issue of Big Ears is further probed. Bruce Goldsmith is a very experienced pilot and test pilot, and from that score I have to take all his warnings very seriously. And I do. Accepting his warnings, does not prohibit me from asking more questions and working out things for myself.

The first question I have is under what circumstances are the Big Ears recommended? Bruce states that in the article that it is an emergency procedure, but does not elaborate on the emergency. It would be very informative for me and other lesser experienced pilots to be told what the emergency could be.

1. Deep Stall on Release of Big Ears

As can be seen from the observations previously given in another article (above), I recommend that when people use Big Ears on landing approach that they should rather land with them in. So we agree on that.

2. Front Collapse in Big Ears

The front collapse with big ears is more difficult. 'Before Bruce' it has been recommended by top pilots and even manufacturers to use big ears in turbulence because the glider is more stable. In excessive turbulence anything can happen, with or without big ears, but it might be LESS likely to happen with Big Ears than without.

The big question is: when can one expect a front collapse to occur when you have big ears in? Does Bruce know of any cases where it has happened, or is this a theoretical assumption?

I use big ears usually only in very turbulent conditions, because I think it gives me a higher descent rate and more stability! My main priority is getting down safely. Generally the wind is also stronger, which means that more often than not I am also pushing speedbar. Only once did I find the turbulence such that the glider was folding more wing or trying to get them out, making it uncomfortable to fly, but I could land safely, albeit in bush on a hill. Even with remembering the glider - a competition glider - doing wild movements, I cannot recall a severe front tuck.

That does not mean that I think it cannot happen for a glider to get a front tuck whilst having Big Ears. It would be helpful to know if Bruce's statement is based on fact or theory.

3. Reduced Manouvreability

I agree. One has less ability to steer with Big Ears and that is one of the reasons I do not often use the manouvre on approach. I prefer to enhance my skills by doing a good basic approach.

Long ago, however, I have read an article from a now-forgotten-pilot about steering with increasing and reducing the tips while flying with big ears. One pulls more on the side you want to turn to plus using weightshift, and you actually have a reasonable control, nowhere near the normal control, but better than only weightshift. The brakes of course, stay in your hands.

To make it more clear: one pulls more (lower) on the lines on the side you want to turn to, effectively making the big ear bigger on that side, while simultaneously lifting the hand on the other side, making the tuck on that side smaller. (Note: you do not need to take more lines in your hand - by pulling more down on the lines, the wing folds further.) I have found this method to give me so much more control that I always use it when pulling big ears.

I would doubt the statement that no top level pilot uses big ears on approach because it is more dangerous. It is probable that they are more inclined to enjoy doing good approaches rather than having to submit to a different technique which is more often used by lesser experienced pilots. Many of them DO use big ears on top landings. Some top pilots use assymmetrics for top landings - not my favourite.

If it was true that top level pilots have real knowledge about the dangers of Big Ears or believed it absolutely, it would have circulated through to the schools and clubs and associations already, to avoid the manoeuvre or at best know what to do. It would have been common knowledge as most top pilots have very good rapport with their clubs, and is listened to as demi-gods. Bruce would not have been the lone voice in the desert. Don't get me wrong: I support Bruce in saying that the manoeuvre can be dangerous. There are just too few who are coming out saying it aloud.

Of course, there may be a difference in his classification of a top pilot and mine: maybe I am referring to very good pilots while he is referring to test pilots.

4) Dumping in Wind Gradient

To this I don't agree. I would say a dumping in wind gradient would most likely only occur when the pilot tries to pump out the big ears near the ground. As stated in my previous observations, this in my opinion is the most common cause of gliders going parachutal from the big ears manouvre and the dumping which inevitably follows.

However, I have to ask the question in order to be able to change my opinion if necessary: has Bruce seen or heard of a pilot being dumped with Big Ears on while entering wind gradient where it was NOT a case of pumping out the ears?

CONCLUSION

While it is very certain that the Big Ears manoeuvre is not without danger, it is still a relatively safe manoeuvre when used correctly. It is also true that many, many pilots are getting away with using the manoeuvre incorrectly, and that this contributes to the large number of pilots who believe it to be danger-free. Percentage-wise the number of accidents occurring from the manoeuvre is really very low, as a guestimate.

While I do not want to diminish the warning which Bruce issues, it will be more to the point to inform and train pilots how, where and when to use the manoeuvre in order to avoid the unnecessary accidents which have been happening world-wide.

Laura Nelson
29 June 1998

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