Much discussion has been had on slipping a B model, that is NOT the question. What about an A model? I have seen nothing about this, and find nothing in the owners manual. Could one surmise that due to the smaller flaps on the A model, that the air would not be as prone to deflecting from the tail?
If there is a thread discussing this, please direct me to that.
Slipping an A model
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n2582d
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Bruce Fenstermacher
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Re: Slipping an A model
As you summarized an A model is NOT a B model. The A model has smaller, less effective flaps than the B model. The A model elevator is NOT the same as a B model though that probably makes little to no difference with the issue the B model has which is stalling the elevator.
How do you stall the elevator? You slip which causes the fuselage to blank out lots of the air that would pass over the trailing half of the elevator. The B model semi fowler flap at 40° is just enough more disruption in airflow to block enough air from passing over the elevator and the elevator stalls. Cessna test pilots discovered this in the B model development and that is why there is a warning against it in the Owners Manual.
Could you stall a elevator on an A model? I suppose it could happen but I don't know how. And if Cessna new about it they never warned us. In my 30 year association with 170s I've never heard anyone who has experianced or even told stories they've heard of others who have stalled an elevator on an A model.
My last 170 was a '49 a model. The airfield we based it at almost required a full flap full slip to get into. I did it all the time and no one I know could slip a 170A harder than I did. If I still had an A model I'd still be slipping it with or without flaps. If I should ever fly a B model again I will us flaps and never slip with them deployed. On a B model the flaps are so effective there is no reason to slip. But truth be told there is only one reason to slip a B model and that is for fun BUT never with flaps deployed.
How do you stall the elevator? You slip which causes the fuselage to blank out lots of the air that would pass over the trailing half of the elevator. The B model semi fowler flap at 40° is just enough more disruption in airflow to block enough air from passing over the elevator and the elevator stalls. Cessna test pilots discovered this in the B model development and that is why there is a warning against it in the Owners Manual.
Could you stall a elevator on an A model? I suppose it could happen but I don't know how. And if Cessna new about it they never warned us. In my 30 year association with 170s I've never heard anyone who has experianced or even told stories they've heard of others who have stalled an elevator on an A model.
My last 170 was a '49 a model. The airfield we based it at almost required a full flap full slip to get into. I did it all the time and no one I know could slip a 170A harder than I did. If I still had an A model I'd still be slipping it with or without flaps. If I should ever fly a B model again I will us flaps and never slip with them deployed. On a B model the flaps are so effective there is no reason to slip. But truth be told there is only one reason to slip a B model and that is for fun BUT never with flaps deployed.
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Bruce Fenstermacher, Past President, TIC170A
Email: brucefenster at gmail.com
Bruce Fenstermacher, Past President, TIC170A
Email: brucefenster at gmail.com
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