REAL FORCED LANDINGS PART II
Are real forced landings different from what we have been taught? Jim has over a dozen of them without scratching an aeroplane so he has a good idea of what works on the day.
Last time I said I’d tell you about seven things you can fiddle with that may restore some, or all of the power, plus the main things to look for when you choose a field.
CAN YOU FIX IT?
The Primer – Confirm it’s in and locked. If the engine has died completely, you may get a bit of power to stretch your descent by pumping the primer. It’s worth a shot.
Mixture – Try smoothly enriching and leaning – either may restore the power. I met a guy recently who did a forced landing because his engine failed as he descended to land at the coast. He admitted he had always flown up-country and didn’t realize he had to richen the mixture as he came down into the denser coastal air.
If a turbocharger fails this may cause the mixture to become so rich that the engine dies. Simply leaning way back can restore most of the power. Twenty-five years ago a heavily loaded Piper Chieftain crashed just after takeoff on the reef, killing all ten on board. Investigators found a failed turbocharger. Had the pilot pulled the mixture back a couple of inches he would have saved seven lives.
Pitch – Try fiddling with it. It’s very unlikely to restore power, but pulling it into coarse will make a real difference in stretching the glide. I’d be inclined to leave it until your final approach and only use it then to adjust your glide path if you need it.
Fuel Selector – Try every position – and give it time to take effect – at least ten seconds. Yes even the off position might give you fuel. I read of a Partenavia P68B that crashed because the selector body, behind the upholstery, had sheered a bolt and swivelled such that the apparent OFF position would actually have been ON.
Fuel Pump – Generally switch it on – but know your aircraft. If you have a fuel injected Continental engine the POH has very specific instructions about when to use the HI or LO position and you can easily cause an engine failure by getting it wrong.
Carb-heat – Yep to melt – or prevent – any build-up of ice in the carb. But it can also be used to restore power if the normal air-intake gets blocked by a bird or by a collapsed elephant trunk (those big red hoses).
The Throttle – Try it from time to time to see if your actions have restored the power.
WHICH FIELD?
Okay dear instructors, I’m sure you know how to choose the best field, but let’s run through some of your options:
Wide fields are a thinking pilot’s delight. Simply fly your base leg parallel to the long side of the field and then turn final when it looks about right.
Narrow fields, including roads, look longer than they are. Don’t be deceived by them
Cane fields are often not the nice soft landing places that they look like from the air. Young cane might be okay but if you land in tall cane it’s like hitting a wall. The stalks all pack up against each other to make a solid barrier.
Roads are great for precautionary landings when you have the power to avoid last minute traffic, road signs and wires. Next time you drive somewhere out of town just count the wires that cross the road – you are in for a shock. I’d rather touch down in my selected piece of veld at 45 mph than fly into wires or a car at twice that speed.
And think about this – if you choose a piece of road and then have to abandon it at the last second, you then don’t have a choice of where you’re going to land – you will hit whatever happens to be beside the road.
Perhaps the ideal place would be a nice wide, straight country road with a good field running next to it – with no wires to hop over if you change your mind at the last moment. But don’t count on finding that field.
When you are training a pupe, if he selects a road, let him go down far enough to see what he would be committing to.
This is a bit of a hobbyhorse of mine. I have had over a dozen engine failures in single engine aircraft – none of them on a road, and none of them even scratched an aeroplane. But that shouldn’t be a consideration. Your job as an instructor it to be sure your pupil makes safe decisions – not ones that save money for insurance companies.
Wind. Even a light wind makes a massive difference. Eight knots behind you rather than on your nose makes a difference of 30km/h to your touchdown speed – that difference on its own is more than enough to kill you.
Obstacles. Trees or wires on the approach dramatically shorten the usable length. We sensibly tend to give them too much clearance. Solid obstacles at the far end hold obvious hazards.
Gradient. It’s difficult to judge slope from the air but it makes a massive difference. Rivers or stretches of green vegetation often give you some idea of the lower ground, so do farmers’ contours. Landing downhill is a terrible idea.
Sun. A dirty windscreen can kill you if you land into the morning or evening sun – you simply can’t see what you are going to hit.
I must tell you about a mate of mine – Bill Fortuin. This happened many years ago. He was about to depart Heathrow for Johannesburg as co-pilot on a BOAC (British Overseas Airways Corporation) DC4. It was his duty to ready the cockpit half an hour before the captain arrived. When the great man eventually entered the flight-deck, he completely ignored Bill and busied himself with hanging his jacket and cap exactly straight on a coat-hanger.
As they would be sharing a cockpit for three days, Bill introduced himself to the captain. The response was, “Mr Fortuin, in this cockpit you may address me as ‘sir’. Outside the cockpit refrain from addressing me at all.”
He then sat down, pulled on some white kid-skin gloves, looked straight ahead and said. “Mr Fortuin, this aircraft is unserviceable. I’ll thank you to have my windscreen cleaned.
After a while a man in a brown coat, carrying a ladder, a bucket and a chamois was summonsed and the windscreen was cleaned.
Not great CRM, but I think I would like to fly behind such a captain. An aeroplane with a dirty windscreen is unserviceable.
And one more story – because I feel strongly about this.
When I was a young second lieutenant in 109 Commando Squadron I had to fly a general to the military airfield at de Aar. As we approached I realized we would touch down shortly before sunset and that runway 30, which was the runway in use pointed exactly at the setting sun.
There was no wind and no other traffic so I requested 12. “Negative, negative, Charlie Mike Victor. Call on final approach for 30.”
It’s no use arguing with the military mind so I told him I would hold to the south of the field until after sunset. I could almost see a massive question mark hovering over the tower. And I could certainly hear the abuse coming from the right hand seat where my moustache-pulling pax was about to blow a fuse. Actually I think he needed to pee.
Habitation. Land near habitation or a road – a ten-mile glide to a farm house is more fun than a ten mile walk in the desert.
Surface. An airfield is first prize, then a cultivated field with a young crop. Cultivated is important because it means the farmer has removed big stones and filled in holes and ditches. Grazing country looks tempting but often has hidden depressions and rocks.
Flaps. If nothing else sticks in your pupe’s head, he must understand the speed squared rule. It says if you double the speed you will suffer four times the damage. Think of a C172. You can throw it on to the ground at 80 mph, break the nosewheel off, go on your back and possibly be trapped in the cabin while fuel runs everywhere. Or you can use full flap, touch down at 40 mph and start planning how you will fly the aircraft out of there.
The choice is yours – it’s that big handle between the seats.
Wheels up or down?
There are no rules – only guidelines, so here’s stuff for you to think about now – not at the last minute.
- You want the aeroplane to decelerate positively but not suddenly.
- You do not want a fire.
- You want it to stay shiny side up.
So let’s think how your aircraft will handle each of those requirements. If it’s a high-wing, fixed gear aircraft like a C172 you want a hard surface where the brakes will work well – that will look after all three of these requirements. Antbear holes, marshy areas and soft sand can put you on your back with a potential for fire as the fuel leaks from filler caps. Fortunately you have huge flaps – use them all for the slowest possible nose-high touchdown.
A low-wing, fixed-gear aircraft would also enjoy a hard surface for max braking. But antbear holes, marshy areas and soft sand will not put you on your back even if the bigger nosewheel digs in, so long as you again use full flaps and touch down at stall speed.
Now let’s think about aircraft with retractable gear like the C210, Bonanza, Comanche, Arrow and the Saratoga family. There are two schools of thought. The first is favoured by the Air Force. They suggest gear down regardless of the surface. If the gear holds up that’s all well and good. And if the gear gets broken off, well at least it helps the deceleration, and if it keeps the low-wing tanks off the ground for a while, that’s also good.
For water landings, low wings are definitely preferable – they are prone to staying the right way up so you can open the door and move out on to the wing and curse your luck while you wave to passing marine craft.
The famous Max Conrad dumped a 250 Comanche in the Atlantic while ferrying it. He sensibly followed shipping lanes – which is much the same as following roads across the desert. He alerted a ship that he was running out of fuel and would be obliged if they could deploy a rowing boat to avoid any discomfort.
This all happened as planned and Max didn’t even get his socks wet while stepping from the wing of the Comanche into said craft. In fact the US navy had to open fire on, and sink, the aeroplane two days later as it was considered a danger to nautical endeavours in that lump of ocean.
Finally, if you are good at sideslipping, that makes forced landings so much easier.
Right, that buttons up forced landings. Now let’s move on to that most noble an ancient craft – navigation.
-o0o-