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Old 21st August 2006 | 09:06
  #24 (permalink)  
Shaggy Sheep Driver
 
Joined: Oct 1999
Posts: 3,325
Likes: 2
From: UK
Originally Posted by Dan Winterland
A lot of PPLs will go "Ooh, taildraggers!" usually accompanied by a sucking of teeth or a shake of the head when the Chippy is mentioned. Don't let them put you off. The Chippy is one of the easiest aircraft to fly ever built- it's just different and it's learning the differences which will take the time. If it seems to take longer than expected don't despair. You will find it will just click after a while. It's an amazing aircraft for instilling confidence and has the nicest handling of any light aircraft I have ever flown. I learnt to fly in the RAF on the Chippy and soloed in 8hr20. Later in my career, I instructed on it for three years and sent some people solo in less time than that. Interestingly, those who arrived with some flying experience in spam cans had no advantage over those with no experience.
A few points:
The taxying attitude is the same as the landing attitude. Remember it. Also, most Chippy accidents happen on the ground. Get the nose weaving and never taxy into an enclosed space without being confident you have room. It's much safer to stop the engine and push the aircraft. Keep the stick back when taxying except when taxying downwind in strong winds when the stick should be neutral otherwise you run the risk of a gust getting under the elevator and tipping the tail up.
The approach speed is 60 knots with full flap. Exceed that by even a couple of knots and you will find it floats and makes the landing harder. Nail 60 knots and you will find it much easier to land. However, it is stable on the approach and easier than a PA28 to maintain speed. The crosswind limit in RAF sevice was 15knts. This is an airframe limit and you will find you will run out of rudder at 16 knots if you try to exceed it in a three point landing. You can increase it by 'wheeling' on and using the rudder/brake, but this is groundloop territory and your instructor shouldn't be teaching it at the conversion stage.
Groundlooping is one of the horror stories you will hear from the uninitiated. It happens because on the ground a taildragger's c of g is behind the wheels and will try to overtake the wheels if there is any drag from them. Prime groundloop conditions are light crosswinds with no headwind. Be aware of it and be prompt with the use of rudder. If it starts to go, don't be too quick to use differential brake - you will proabably exacerbate the situation. And if you do groundloop, don't worry. The aircraft is very strong and damage is unlikely with the castering tailwheel. I have experienced maybe a couple of dozen with no damage.
Be careful about using the brake lever on the ground. Use if harshly on the landing roll, you might find the tail lifting. And if you have any rudder applied when you use it, the brake will come on that side first.
You will fly aerobatics - the aircraft is designed for it and it's delightful. In the RAF syllabus, students often could fly a loop before first solo and were cleared solo aerobatics at 30 hours. However, it's not an Extra 300 and those aeros will have to be gentle. Pull lots of g at once and you will lose too much speed and use up lots of valuable height. The engine has a basic carburettor and will stop when inverted. It stops because the float goes to what is now the top of the float chamber and opens the jet fully. This leads to a 'rich cut' and too much fuel is the reason for the engine stopping. Close the throttle while inverted and you will find the engine picks up much quicker. Learn stall turns to the right first. Going left is opposing the engine rotation and much harder. If you mess up an aerobatic manouevre and think you're going to tailslide, hold the controls very firmly in the central position. If they 'snatch' to full deflection, airframe damage is probable.
The Chipmunk spin is very stable. It was cleared up to eight turns in RAF service, four turns loses you about a 1000' with another 300' for the recovery and is much more comfortable. The Chippy incipient spin stage is the first 360 degrees which is easily recoverd by centralising the controls.
Enjoy!
A very interesting post from Dan Winterland. It's interesting what you say about the crosswind limit - I landed our Chippy at Liverpool earlier this year on 27, with a steady surface wind of 360 at 15. There was an Easy Jet 737 at the hold, and I could see two anxious faces in its cockpit looking up the approach at the Chippy coming in almost sideways! You could almost see the thought bubbles "I hope he doesn't crash and block the runway". The landing wasn't my tidiest, but it was controlled and safe.

A few weeks later I was showing members of the Aircrew Association around Concorde G-BOAC at Manchester. I was on the flight deck chatting to one guy who, it turned out, had zillions of Chipmunk hours from his RAF service. "What would you say is the crosswind limit of the Chipmunk?" I asked him. "15 knots" came the immediate reply.

I've only once, in 27 years of Chippying, felt the tail rise unexpectantly. I was taxying on the apron in a brisk tailwind with the elevator held neutral, when, despite my feet resting on the pedals, a gust blew the rudder to full deflection. That put the brake on hard on that side, and I felt her start to rise. Rapid centralising of the rudder restored things to normal.

It is interesting what Dan says about use of brakes on the landing roll. There was some discussion (I think it was on here) a while back about the RAF insisting on landing with some brake set. I was and am very much against that, since it diminishes rudder movement. I think it's much better to have full rudder available when landing (and also when taking off - final 'brakes fully off' check before rolling), and it that's not enough, you just gently pull back the brake lever with the little finger of the left hand (don't yank it on!), holding the 'lock-on' collar down with that finger as well so you can apply and release small amounts of brake nice and easily and gently. You'll already be holding full rudder, so only the appropriate brake will be applied.

Wheelers are nice in the Chippy. With a good headwind down the runway you can actually come to a stop with the tail still up. And another trick for when you have more experience - tail-up taxying. You can taxy very fast and see where you're going with the tail up, and I do it at Liverpool if there's some distance to go to vacate the runway. But you have to be careful - that really is groundloop territory if you're not careful.

Use of T/O flap is another bone of contention among Chippy pilots. I always use one stage of flap at short field, no flap at big places like Liverpool.
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