fire / safety discussion threads

[Learjet]

Hub-bar has hit the bulls-eye here!

If however you find yourself in a behind the power curve or downwind dragon situation, the throttle is wide open, turbos are engaged and you are instinctively going to try to fight your way out, right up to the point of possible impact. There is probably no way in these situations that you are going to willingly close the throttle before impact.

This scenario is one that I believe is so absolutely typical of the type of "mushing into the ground" after take-off accidents that we are seeing too regularly at the moment. I've said it before and I'll say it again:

Current gyro training & instruction in South Africa is NOT adequately teaching students to recognise when they're flying behind the power curve - or how to properly fly out of it. Too much theory and "head in the cockpit fly-by-numbers" instruction and not enough practical fly-by-the-seat of your pants demonstration of it; "can you feel it now, we're getting behind the power curve...yes it feels like a downdraft but we're really losing lift and thus altitude because we're behind the drag curve... so here's what you need to do..." instruction.


Recognising and averting the behind-the-power-curve pitfalls which are the root cause of too many gyro accidents and the post-impact / roll-over fires is going to require a training solution rather than just a technical construction solution.

[t-bird]

Hi Len don't blame training for flying behind the curve.We had Eben snr who is one of the best instructors flying behind the curve last year.Johan Stemmet done the same a few years back. I have done it.

[Learjet]

Hi T-bird... we've all done it. But if it still catches out experienced pilots - then it's little wonder that the guys with fewer hours and less experience get nailed by it. We can install armour plated fuel tanks in gyros - but if the guys aren't being trained to an adequate standard that's not going to stop them pranging in the first place. If not by improved training how do we rectify this situation?

dave

[Gyronaut]

Hi Len don't blame training for flying behind the curve....

Um, Callie, I didn't but I will. Nobody flies behind the power curve intentionally (unless training) but it continues to happen.
We're all human and we let our senses rule. Humans, being the wonderful creatures we are, are capable of learning to look out for the warning signs, heed them and avoid an accident. I think this is what Dave (Learjet) is saying and I concur wholeheartedly. Training (maybe even refresher training) is the most logical place to begin.

You can do it on your own (and we should from time to time). Select a suitably safe area climb to 1500' agl, (Do HASSEL checks of course), come to a power-hover into wind, wait for a good rate of descent to develop, check alt @ recover. Check alt again when at cruise speed. So you needed something between 150' to 300'? Great. Back up to 1500' now fly 50, then 45, then 40 then 35 then 20 then 10 maintaining altitude. Soon you will be at full power, descending. Checking descent distance after recovery go do the same downwind. Not surprisingly you may be surprised at how much more altitude you 'appear' to lose when doing it downwind. Soon you will be doing it with the same results regardless of wind. Bingo! Safer you are already!

Fly safe.

[t-bird]

Sorry Len got confused with you and Dave. All these gyro avatars look the same.

I am saying that training is more than adequate on Gyros to identify flying behind the power curve and recovering.
When you have a GPL you have the tools to fly but not the EXPERIENCE.

The problem comes in when you take your gyro and do some game viewing or looking at the scenery and turning.

An experience pilot will identify the problem when it start and inexperience one will identify it when it is too late and get sucked into that downdraft.

I know of one instructor who closes the gyros airspeed and altimeter to get the trainees head out of the cockpit and help them develop a feel for the gyro. THIS IS ONLY DONE WITH THE INSTRUCTOR AT THE REAR SEAT!

[saraf]

Anti-theft 12V solenoid valve for petrol and diesel. Cuts off fuel when not energised. Bore of 3.5mm. Pressure 0 - 3 bar, flow coefficient of 0.28. 8mm OD. Protected to IP65.

[Gompou]

Hi saraf
Now you just need a way to energies the solenoid in case of impact.If you install it between the fuel pump and the injectors with a back flow to the tank, it will probable relieve the pressure in the line before it could rapture and make a vapor. you still need to cut the power to the pumps in the same time.The positive here for me is the fact that the solenoid would be close under normal flying conditions and therefor the chance for malfunction in flight is minimize.
Fly safe
Gompou

[Hub-Bar]

I am surprised by the lack of instructor inputs re the training suggestion. Anyway, maybe they don’t follow this forum’s discussions. For the benefit of all the other ordinary gyro pilots out there like me, I would like to repeat : ‘I suggest that we incorporate into our training programs a drill which dictates that when encountering ‘perceived power loss’ situations close to terra firma to immediately take your left hand off the already fully open throttle and place it on the master/ignition switch READY TO SWITCH IT OFF (the switch which kills the engine, fuel pumps and all electrics) just before unavoidable impact.’ This might just save you some skin one day when things go horribly wrong.

This week I have had lengthy discussions with the Mockes in Uppington as I fly a RAF2000 and although the RAF does not have a record of ensuing fires, it remains a very real possibility and concern to us pilots and manufacturer. I am busy with a design to prevent fuel leaving the PE fuel tank via the filler pipe entry/fuel cap in the event that any of these components came adrift in an accident scenario. The basic idea is a simple polyurethane ball valve (which lives at the large diameter inlet inside the tank) which will plug the inlet hole as soon as fuel starts rushing out there. The concept seems feasible but it is early days and I will keep you posted re progress. (Any other practical concepts? Please contribute if you have an idea!)

The other idea is to install normally closed electric fuel cut-off valves at the two outlet points on the tank. The idea is that when the electric power is cut, the dual fuel outlets on the tank is shut off. Dual redundancy, independent wiring, pilot lights indicating each solenoid’s energisation status as well as a fuel pressure gauge upstream of the electrical fuel pump will be required. Yes, the fuel will shut off in the event of a total electrical power failure, but so will the engine given electronic ignition/ECU as in the case of the RAF. Saraf has posted an example of such a solenoid valve. The search is on for the most suitable one on the market. Any suggestions? Ok, so this is the first line of defense – we must try and keep the fuel in the tank and then hopefully the tank holds together.


Regards

Francois Marais

[Gyronaut]

Forgive the silence - time flies, we're flying!

On this topic I would like to add 2 things. The first is that it is an instructors job to teach sound decision making related to flying. It is this kind of discussion that adds to the parameters of our decision cycle. We can be told 100 times to do something yet, without the benefit of understanding, it will not influence our decision process. Once we KNOW we will do it. The second point is that I am keen to hear what the best potential solution is. Is it not perhaps a fuel cutoff solenoid AND a fireball? Fuel cutoff does its job if the tank doesn't break, fireball is second line of defense, in case it does. ?

What say you?

Gotta go fly.. bye