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Red Line

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Creator of this place
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Jan 1, 2006
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Austin, TX
Randy couldnt upload this, so he asked me to. Randy please edit this post to suit.
n issue 4 (October 1983) of the Acro Sport Newsletter page 11 item 12 Ben Owen had a technical tip regarding the Acro Sport 2 instrument markings. He indicated that the maximum never exceed speed is approximately 180 MPH. The article also lists other neat information. Of course these are only guidelines, we as the builders set the parameters.I have attached a picture with the text of the article.
Carlos Duenas

Steve Manweiler <[email protected] wrote:

Tom is correct that it is your airplane and you can set the redline to where it has been demonstrated during the test period. All that aside I arbitrarily set my redline at 165 MPH. During the test period I brought the airplane up to 165 in steps starting from 140. I did the "strike the stick" thing to induce flutter and tried to get a feel for what the airplane was feeling like during this testing. Sort of subjective but the airplane will begin to "talk" to you as the speeds get higher and at some point you will want to say that is enough. I took the airplane to 170 MPH and at that point I said that was as high as I wanted to push it. I do mean "push it". At 2500rpm I needed 45 degrees nose down to get to the 165 MPH indicated. I started my testing at 6000 AGL which is about 7400 MSL in the Wichita area.

I have heard some of the guys talk about cruising at 140 MPH. My airplane cruises about 120 MPH. this is open cockpit and fixed pitch wood prop.

I can loop my airplane from level flight starting at the 120 MPH indicated. You do get more float over the top if you use 140 to start. I basically fly my airplane at or below 140 MPH. I can do all the manuevers including hammerheads and half cubans using this speed at entry. By the way the Acro II does hammers really nice- feels real nice when you rotate out feeling like you are rotating around a pin.

I have not had my airplane to 180 to know if it reaches terminal velocity at that speed or not. I do know that for my airplane 165 is a very reasonable redline for VNE. I would suggest setting the redline at 165 on the instrument and if you feel comfortable taking it higher during the test period you can do so and enter it into the logs. The lower instrument redline might keep someone else from abusing your airplane.

What do you think?



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