Thought it was interesting to see many FRC components used in the design of the landing gear for this aircraft.
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Probably FRC alumni
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“hey uh… did we burn flash the landing gear spark max?”
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I’m sure (or I certainly hope) this is just a prototype and while I don’t mean to be mean VEX/REV, but I would absolutely NOT trust a Versaplanetary gearbox and Neo550/Bag motor to run an aircraft landing gear system.
They’re great for FIRST applications and I use all of them a lot on our robots, but the reliability factor of aircraft needs to be like orders of magnitude higher than FRC applications
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To be fair, I’m sure both companies also would prefer not to be a part of any future news reports regarding an aircraft landing gear failure due to its use of a component rated far below what you would want for something that important.
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You might be surprised at how flexible US regulations are regarding amateur-built aircraft.
Amateur-Built Aircraft | Federal Aviation Administration (faa.gov)
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Yeah, this has been brought up before. I don’t have the thread offhand, but there’s a 10:1 VersaPlanetary stage (ya know, the one we all avoid) in the landing gear iirc.
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One of my instructors back in flight school (long story) years ago used to tell this story about how he had built an ultralight one time that used a Snowmobile engine for propulsion.
Long story short, snowmobile engines aren’t built to the same reliability/redundancy standards as aircraft engines, so one engine failure later my instructor and his ultralight were stuck up in some trees, uninjured, but vowing never to do that again. Others have been less lucky. 
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the plane: 
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Yeah, @RoboChair’s old startup deployed BAGs on 10:1 Versaplanetaries to a (non-safety-critical) product, and the runtime turned out to be measured in minutes. My old company bought that startup anyway, and at some point after that they had the funding to replace that motor/gb stack, so it all worked out…
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I’m still curious what team these guys are from. Bless them for using a 10:1
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It was like 40 hours of run time till they had to get refurbed. We may have been a known name in the VEX office for a while…
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So, 1 work week in y’alls application, but these guys might not be completely hosed if they put in PM in the ~20 hour range, since you’re only running the gear a couple times per flight…
Of course if any shock loads are running back through that linkage to the GB during landing, all bets are off.
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Landing gear are generally designed such that when they deploy or retract, they lock into position so that they don’t rely on the drive mechanism to make them safe. That is the case with this design here so I wouldn’t expect the gearbox to take an impactful load when landing. That said, they will certainly have plenty of opportunities to test their emergency landing gear deployment mechanism in their development process.
I have been following this company for a while and for the most part, these guys seem to be making reasonable design decisions. There are certainly some non-conventional decisions they are making such as mounting the avionics on the canopy via an umbilical cable and the split rudder. some of their decisions will result in anomalous behavior so it will be interesting to see how they deal with that in testing and design refinement. I did I reach out to them when I saw the video to give them some feedback about their selection. They were aware of the shortcomings and claimed to have a more permanent solution down the road. They also mentioned that the design came from an Intern who had FIRST experience, implying that they did not have the experience with FRC themselves.
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We don’t even trust VersaPlanetary gearboxes on our robots, lol. Our team Wiki (which doesn’t have much in it) has this as the only entry for VPs:
“They aren’t too great.”
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A friend of mine has been an aerospace engineer working on passenger aircraft for the past forty years as part of three major airplane manufacturing companies.
He absolutely refuses to fly.
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Does he say why, is there something I need to be worried about /j
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He does: he knows many of the people who design and build these things. He trusts none of them to wipe their own backsides, much less create a flying machine that doesn’t catastrophically fail at an alarming rate.
Now, that said, I fly all the time, and am not worried about it any more than I am the deer slalom that is my morning commute.
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