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Well done Phil (its the only way to get a web page all to yourself. Webmaster Dave)

Phil Alexander aka Psycho is now a qualified holder of an NPPL(SLMG) and has the
supporting medical documentation enabling him to fly passengers.Congratulations Phil. regards JB

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Motor Glider operations by Phil Alexander

I thought I would start my first foray into literature (after nearly 30 years writing dry as dust technical reports) with a brief talk about the operation of the motor glider. Many of you have flown in it and hopefully the rest of you will get the chance to do so over the coming months.

It may seem like stating the blindingly obvious but its operation, especially on the ground and on take off, is quite different from the gliders. The difference is of course the engine, connected to that vulnerable and very expensive bit of kit the prop. This engine is a VW flat four (for details see Taff or John who understand these things), even the fuel cap is marked VW! This I believe is the engine in the original beetle and even the VW microbus so it’s a well-proven and reliable powerplant.

The thing is that even though we operate what is basically a car engine we cannot and do not treat it like a car engine. When you get in your car you just start it up and drive away. We on the other hand have to warm the engine up before we can even taxi the aircraft. This can take some time and you may well have seen us run the engine for 10 minutes or so before we move at all.

Even after the engine is warmed up before we can take of we go through a series of checks to ensure that the engine is developing full power and running normally. You will have seen and heard us do this when the engine is revved to maximum power whilst the spoilers are held open, then after a few seconds, the engine is throttled back to idle. Only once all these checks are done are we ready to take off.   

So we sometimes can’t take advantage of what may be a brief lull in normal operations to take off because either the engine isn’t yet warmed up or we haven’t completed the full power checks. Additionally we can’t take of if a cable is out. This is because of the risk of fouling up a cable, probably on one of the outrigger wheels.

When everything is clear then we can move for a take off and you will probably have noticed that we do a rolling take off if at all possible. The important thing is that no one on the airfield can actually legally give us permission to take off.

That’s because we do not have air traffic control who would actually have the legal power (and responsibility) to give such permission. So each take off is at the motor glider pilot’s discretion and he has complete responsibility for it. Legally I believe you may be able to say on the radio “take off at your discretion” but the best thing is to say nothing, except of course to radio “stop” if you see a potential problem as we move out to take off. Our radio is always set to 130.1 at Upwood.

Once we are rolling take off comes after just a few moments with a ground run of 100 to 300 yards depending primarily on windspeed, cockpit and fuel load. We generally climb out dead ahead to about 300/400 feet and then turn to fly downwind climbing all the while.

The direction we normally turn is to the right when taking off on 24 and to the left when on 06. This is because turning in these directions takes us away from Upwood village and Upwood airfield houses respectively. Thus we avoid annoying the neighbours with too much noise, or by crashing into their houses if it all goes horribly wrong. We would only turn another way to take avoiding action.

We then turn to fly downwind staying close to the airfield all the time. The reason for this is simply to ensure that we have the best chance of making it back onto the airfield safely in case we loose the engine. Of course if the engine fails during the initial take off then I will just land straight ahead. If we are high enough (about 500 feet) and if there was no significant headwind we could just do a 180 and land back down the field or do an abbreviated circuit. Above that height if we loose the engine we can just land normally as we would be flying down the downwind leg anyway.

Having reached the end of the downwind leg we should be well above circuit height (around 800 feet) at about level with the launch point. At this point we can either go backup the runway (or alongside if a launch is taking place or is imminent) or just take any lift going and climb away. On a lift free day when flying back down, or parallel with, the runway I will normally change the prop to coarse pitch for cruising and then set off on track.

But when there is lift then why use that noisy polluting engine. So we try to turn it off as soon as possible. Again we can’t just turn off the ignition straight away as we have to let the engine cool down for a couple of minutes at least.

This is because of thermal shock to the engine. If you turn your car engine off your car will come to a halt and the flow of cooling air over the engine stops. In the air the cooling flow never stops so we have to lessen the engine temperature gradually. A cooling flap at the bottom of the engine compartment is also shut to minimise airflow over the engine and reduce the rate of cooling after engine shutdown. Nevertheless the engine still gets cold quite quickly after shutdown in the air. Once it is cold then we have to warm it up again before we can apply significant power to maintain height, let alone climb.

You will all have seen that we almost always land the aircraft with the engine off. There are two reasons for this. Firstly philosophical, we are all glider pilots and gliders don’t have engines. Secondly practical, with the engine off the prop is feathered and positioned horizontally. If one of us should land heavily and collapse the undercarriage or nose over then the prop is out of harms way. If it should be turning then you can kiss goodbye to two grands worth of prop and the same cost again for a shock loaded engine, at least! 

So when we are in circuit the aircraft is for all intents and purposes a glider just like any other. I would not want to be trying to start the engine as I turned downwind (much less on the diagonal leg) and even if I could, unless the engine was warm I could not apply much power without potentially damaging the engine.

So when you see the aircraft in circuit either from in the air or from on the ground, remember starting the engine and going around again is not an option except in dire emergency, so please treat us just like any other glider at that moment. After landing you will have seen us start the engine and taxi away but again we may have to wait for the engine to warm up, at least a little, before we move off. 

Flying the motor glider is great fun and its engine confers great flexibility, but not without imposing some demands. If we are all aware of these requirements we can minimise or eliminate any conflicts between the operations of all our aircraft.