V Speed Validation

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cdoughty
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Re: V Speed Validation

Post by cdoughty »

I'm a scientist/engineer so I love taking data and making pretty graphs as much as anyone. I naively expected to go out and in a 1/2 hour get enough data to make a nice plot and pick off all the speeds. Found out it takes more work than that to do it right.

Since then whenever I fly I always seem to find something else I would rather do :D . And I feel I know the speeds for my airplane, with my ASI/pitot anyway.
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maverick_fa
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Name: Mat
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Aircraft Type: One Forty 100
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Re: V Speed Validation

Post by maverick_fa »

a64pilot wrote: Wed Mar 23, 2022 10:43 am we used a flight test boom with an articulating “bird” as a pitot tube but that was the only test gear, it was all done with regular instrumentation and a stop watch. FAA required instruments calibrated within the last 90 days
Cals timing changes from a sensor to another (stain gauge vs pressure transducer). Mini-Boom is often use for side/forward slip data & airspeed is validate by a redundant system (ie DGPS) linked to the ADAS (FTI).
I want your job... testing an AG AC... WOW!! AG are cool! :D
a64pilot wrote: Wed Mar 23, 2022 10:43 am honestly for basic stick and rudder aircraft like a 140 or an Ag plane, close is good enough. You fly hand them by seat of the pants and with some experience you go by what feels right.
I totally agree but I’m a geek & I like data & flight testing! :P
a64pilot wrote: Wed Mar 23, 2022 10:43 am I’ve got some book somewhere that says best rate climb speed is 73, but in my airplane it is a little over 80 mph, maybe my metal wings are the difference?
-They are mentioning the ‘’RATE OF CLIMB & SPEED for BEST CLIMB’’ @ 81 mph on the top of page 12 but I never understood the difference with the famous 73 mph.
-81 mph is closer for the 67 kts from the C152.
-Or maybe it’s affected by the way your ASI is hooked up to our SUPER DUPER static… :P

cdoughty wrote: Thu Mar 24, 2022 7:48 am I naively expected to go out and in a 1/2 hour get enough data to make a nice plot and pick off all the speeds. Found out it takes more work than that to do it right.
I love Flight Science even if it’s not my field of expertise… there is so much stuff to learn is that area!
Mat | CSG3
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