daniel@petrus.UUCP (Daniel W. Nachbar) (01/30/86)
Many thanks for all the nice responses about the differences between landing gliders and power planes. I'm afraid my question was poorly worded. Let me try to clarify. I hold both glider and power ratings, so I am well aware of why gliders have spoilers. My question is why power planes DO NOT. I recognize the fact that there is less need. I also realize that they must add some cost. However, given their benefits (see article below), I have often wondered why they are completely absent (well almost) from prop planes. please note: > The WWII Taylorcraft spotter plane (I forget the military designation) > had two neat features: an aft seat that turned backwards, allowing > the spotter to spot through a big greenhouse window; and spoilers. > > Between the spoilers and frowrd slip, the sucker could land anywhere. > > The aircraft can be certified for civilian use only if both these > features are disabled. > > phil Why would such a lovely thing as spoilers be disabled? Certainly it doesn't cost anything to keep them there? Is it generally believed that spoilers make a plane harder to fly? My impression is exactly the opposite. Also, a pilot friend who has flown the new mooney claims that it is wonderfully easy to land. set the power, diddle the spoilers, and you land right on the money; just like a glider (he's glider rated as well). I get the feeling that there is some reason for not having them other than cost. Thus, my question to the net. Dan Nachbar Bell Communications Research Morristown, NJ bellcore!daniel
rgg@ganash.UUCP (Rich Giannotti) (02/04/86)
I think the Taylorcraft L2M (DCO 65) needed to have the spoilers wired shut to keep a non-attentive pilot from attempting a take off with them open. Since you can't see them from the driver's seat like you can in a sailplane, I assume the FAA took a "better safe than sorry" attitude. I think the absence of spoilers on most powered airplanes is simply that they don't give enough of a performance benefit to justify the extra cost. As someone pointed out,powered airplanes need to slow down and come down to land,while sailplanes need to speed up and come down. Flaps do the former well. The addition of spoilers helps control the glidepath without pitch or power changes(Direct Lift Control on the L-1011),but I think this feature is not cost justified in the eyes or wallets of the pilot population. The use of terms like "I think" and "I assume" was intentional. Rich Giannotti