Collision detected!
Now that most of the glider's flight control linkages have been bolted, I'm starting to check for conflicts, rubbing, bumping, etc. Some places have multiple moving parts in very cramped quarters, or moving parts that come very close to stationary parts such as bulkheads..
This video shows one collision. (It's in the 'mixer' section of the flight control linkages, in the fuselage just behind the landing gear.)
Fortunately, this one is easy to fix...swap the bolt and nut on one part.
There is much more checking to be done throughout the glider....
#AvGeek #Aviation #ElectricAircraft #ExperimentalAviation #Homebuilt #Glider #DIY #Collision #Bolt #Clearance
TomKrajci 🇺🇦 🏳️🌈 🏳️⚧️
Unknown parent • • •@Simplicator
Good question.
Here is the condition inspection checklist for experimental aircraft:
eaa.org/eaa/aircraft-building/…
It doesn't mention load testing.
The first/prototype of the glider I'm building (HP-24) had the wings static load tested (scroll down a bit for the start of the static testing. Before that is lots of prep/jigs/fixtures/etc.)
hpaircraftblog.wordpress.com/2…
My spar was made with more carbon, so it should be even stiffer. I have not static tested my wings.
I have static tested the tow hook release to ensure it would not rip out of the fuselage under a 1,000 pound load.
When I start flight testing, it'll be slow taxi tests.
A car/truck will pull the glider at moderate acceleration. At 10 knots will the tow release work? Will the wheel brake stop me?
2nd taxi test will feature aggressive acceleration of the tow car/truck to see if the hook release works under a bigger dynamic load. And another test of the wheel brake at perhaps 15 knots.
continued....
Wing static test
HP Aircraft, LLCTomKrajci 🇺🇦 🏳️🌈 🏳️⚧️
Unknown parent • • •@Simplicator
(2 of 2)
My landing gear has supported the glider while I loaded the wings with max water ballast load...420 pounds. Gross weight (minus the pilot) is around 1,000 pounds in that configuration.
My first test flights will not involve any gear retraction. They will be to evaluate control authority, control feel, stability. (Example: to keep nose level in horizontal flight, do I need stick centered, stick well forward, or stick well back?)
It will be like this:
youtu.be/87ya6_aiuUk?t=92
I won't test gear retract until I get at least 1,500 feet above the airfield. That gives me altitude/time to get into the landing pattern if gear retract does not work. (Don't troubleshoot in the air. Get on the ground and then troubleshoot.)
The landing gear is based on an even earlier glider design (HP-18), so it's a design with lots of hours/landings/tests already.
Did I build the landing gear correctly? Set up the travel range and stops correctly?
See graphic for gear layout.
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youtu.beTomKrajci 🇺🇦 🏳️🌈 🏳️⚧️
Unknown parent • • •@Simplicator
It depends on how much time, effort, money you want to spend on testing of individual parts or fully assembled systems.
The folks at Akaflieg Karlsruhe have access to more resources that a 'garage hobbyist' like me. Some of their blog entries show rather fancy test setups:
akaflieg-karlsruhe.de/category…
Dark Aero is doing extensive testing...such as drop testing their landing gear over 100 times! And sharing what they've learned:
youtube.com/watch?v=gjT9P1uEyE…
Yeah, if you skimp on testing...you tend to get more surprises in the air. If you test more on the ground, flight testing tends to be less 'exciting'.
context.reverso.net/translatio…
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