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Am I missing this in the plans...? Cannot find any reference in my fairly recent plans (less than 2 years) - scratching my head about that...
Dave from Maine
Dave from Maine
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My Patrol is placarded for 165 mph (144 kts) Vne -
IMG_0570.jpg IMG_0572.jpg
Unless there has been a subsequent EN/ECN, etc., Vne is 175 mph CAS per the Patrol Book with 4 mph reduction in CAS per 1000' above 8000' per 1/21/2013 EN (Noted as Feb 2013 EN on www.bearhawksafety.com).Last edited by SpruceForest; 05-11-2024, 09:02 AM.Comment
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I'd like to add...P.70 of the Patrol book has a flight test evaluation by Greg King. On p.72 he documents a lot of V speeds in addition to Vne. These came in helpful for marking the airspeed indicator.Brooks Cone
Southeast Michigan
Patrol #303, Kit buildComment
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I can’t say I’m interested in doing it, but for “your information only” ;
Every experimental aircraft built outside of a factory has some value of difference to other builds of the same model.
As such, there is value to the statement made by those following the letter of intent, that says “you shall mark your speeds as you or your test pilot has personally verified”.
The point is this is if your aircraft was only test flown to 150 mph in its current configuration, than it should be marked with a VNE at 150. This provides a speed for other pilots to safely operate it without being a test pilot as well.
So that said, while I would happily work up to and past 150 mph on your build, I find it unlikely that I would don a parachute and perform a flight program to the printed VNE as the reward doesn’t exceed the risk.
I have probably been at or over 165 once or twice in a patrol but I’ve never touched 170. Why? Because whoever set up the v speeds in Marks patrol set it at something below that (as I recall). Did they fly it those speeds prior to setting them,(?) no, not very likely.
And so because of this I may have been a test pilot and not realized it. Am I concerned, no. But you get the point. It’s really only tested to what ever you test it to.
So not to dampen anyone’s mood ir enthusiasm, just be aware of setting limits based on general data that is non-specific to your build.
And to repeat the disclaimer so not to be hypocritical, no I don’t plan to test fly my build to the printed VNE. But if I ever push what ever limit I have set I will re-mark it to the new tested limit.
…or hire a test pilot.
pb
Last edited by 500AGL; 05-15-2024, 04:56 AM.Comment
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Playing around with experimental airplanes makes you a test pilot:-) everytime you go wheels up imhoLast edited by Sir Newton; 05-15-2024, 04:54 PM.
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Have to agree with the Bearhawk's resident knight-errant; every flight is a test flight in an EAB, and the less of the flight envelope explored with that aircraft, the more important the prep and planning. Fortunately, that lengthy period of assigned area flying after getting the thumbs-up allows a thorough validation of the airplane's numbers. If nothing else, exploring the corners of the flight envelope in a planned, consistent fashion is one of those things that is designed to develop some confidence in operating the airplane, as well as highlight issues that suggest some fine tuning of airframe rigging, engine cooling, etc.
To paraphrase one of my undergrad instructors, 'the corners of the envelope want gentle exploration, but explore you must if you ever have need of flying the aircraft to its limits with eyes open.' Some aircraft make it fairly easy to step over the line and spot check whether that design safety factor is there for a good reason, so do it with intent as part of a planned, well-considered test program.Comment
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It’s not always just EAB.
If you’re not familiar with the aircraft you’re going to fly, always spend some time to learn about it before hopping in.
Mark Murphy, who happens to live up here in the northeast, had such an experience and lived to talk about it.
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