props aircraft question

Not silly at all.

It depends on the aircraft really.

Most two engine aircraft these days have their props going in opposite directions to each other to counteract engine torque issues.

I believe the P-38 had both its props going in the same direction (I'm not sure which)
and I know the Grumman Tracker had its props going both in the same direction with a special gadget on the rudder to offset the torque.

As for single engine aircraft, I'd say it really depends on the aircraft, its engine and who made them.

I've heard that the Rolls Royce built Merlin Engines had their props geared to go one way, but the American Packard built Merlins were set up to have their props going the other. Sounds silly to me and I'm sceptical about it (maybe just some old veteran pulling a young guy's leg), but then again, you never know.

I know that isn't much, but I hope it helps

Most US aircraft have the the engines rotate clockwise (from the pilot's perspective). British and Soviet engines usually rotate the other way. However, there are SO many exceptions that you MUST check good references. Twins will sometimes have counter or contra-rotating propellers for torque problems, but most often not. The fancy gadgets most usually used to offset torque are the pilot's feet, as long as the design provides a big enough rudder, and you keep the speed well above Vmc.

Keeping all the engines rotating the same direction makes a lot of sense from a maintenance standpoint, otherwise you have to stock a left rotating starter and a right rotating one, vacuum pumps, magnetos and on and on!

I think it was just the early P38's which had both props turning the same direction. I believe the later marks had them turning in opposite directions though. Could be wrong

PS By the way, it's easy to tell which way they turn. Just look at which is the leading edge of the prop blade, and thats the direction it turns

The first P-38's had counter rotating props to eliminate the "critical" engine out with torque from your good engine raising the wing of your dead engine. However tail buffetting problems cause the roatation to be the opposite (still counter rotating) in all later models so both engines became "critical". To the novice P-38 pilot this was deadly since in most twins only the left engine was the "critical" engine not the right too! This was a contributing factor in the fatal crash of the P-38 "Scatterbrain Kid".

As far as I am aware, RR and Packhard merlins rotated the same way, although an anticlockwise version was produced to give a counter rotating pair for the Dehavilland Hornet/sea hornet. Griffons however rotate anticlockwise making the torque effect on later spitfires opposite to earlier marks.

Just looked at some pictures of early Spitfires, Hurricanes, Mosquitos, Lancasters and P-51s. Their props all rotate anticlockwise.

If you want to realy confuse people build two Sopwith Camels one clockwise the other anti.
The original Camels had a vicious climbing left hand turn due to the gyroscopic effect of the rotary engine. The Germans got tto know this and refined their tactics accordingly.
The Brits then started fitting engines that turned in the opposite direction to nullify the German tactics. Cunning what!
Dai

Chris,

Were you viewing them from the front or rear. If from the front that would be the same as clockwise from the pilots view as stated before by Ashley.

Regarding the P-38, the first prototype, the XP-38, had the props rotating inward. The next prototype, the YP-38 had them rotating outward and they stayed that way for all subsequent versions. The reason for the change was because the propwash from an inward turning prop would cause the wingtips to stall early, and flip the aircraft on its back in a tight low speed turn, or an engine out situation, especially when turning into the good engine. I know of no P-38 variant in US service that had the props turning the same way, however, the Lightning I built for the RAF had both props rotating to the right, as stipulated by the RAF.

Check this:

http://home.att.net/~jbaugher1/p38.html

stinger