Design Debrief

After three months of design, 2.5 weeks of building, and endless stressful nights; our plane finally took off yesterday!

Here’s the final product. I can’t say it’s a very good looking plane… at all… but what matters is that it flies, right?

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So there’s the flight. It went really well for the most part, until the crash landing at the end. For people that understand engineering terms, here’s a not-so-short explanation. We purposely loaded the cargo farther forward to increase our static margin, which is required for static stability. It’s what happens to your aircraft when it’s disturbed from equilibrium – does the perturbation just keep growing, or will it return to equilibrium? So anyway, we knew our static margin was a bit low, so we did that on purpose. That made the aircraft stable… until it needed to land. The pilot turned the throttle (speed) down by about a third, and it seemed to be okay. When he turned it down even further, the airplane pitched down and since it was nose-heavy, it just kept pitching… all the way until it rolled over. At that point, you lose control authority and the plane just crashed.

We definitely had the most epic crash though! We ended up on the roof of a building. Took us a while to scavenge it out. When we found it, it was completely shattered. The funny thing is, this was actually one of our conscious design decisions at the very beginning of the project – do we want to make a very sturdy plane that can withstand crashes, or do we want a high performance plane that will achieve us a good score? Because a sturdy plane would require heavier materials, reducing the flight score. It just so happened that we were unlucky with the loading.

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The pilot is actually really skilled; even if our plane were unstable, he would be able to keep it in the air by actively controlling it. But there is a bonus score for stability this year, so it was important for us to get a higher bonus and improve our flight score.

With the other teams…

Team Tie-Fighter (Conventional)

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This is the only conventional plane for this year, and also the only one that was successful in a full run – as in take-off and landing without surprises. There’s nothing much to say since it’s so conventional, except that on their third run, they overloaded the cargo (on purpose, since they already had a good run) and it ended up nose diving.

Team NARD (Blended Wing-Body)

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This BWB was one of the most exciting to watch, because it flew so fast! It just zipped around everywhere. Unfortunately, it suffered the same fate as our plane, as it also crashed on its maiden flight. The only difference is that theirs crashed into the parking lot, and missed hitting people by about 5 feet. This was easily going at 80 km/hr, so you definitely wouldn’t want it hitting an unsuspecting person on its way down.

We also caught the pilot interview on film, and he explains why it crashed. Our plane essentially crashed in the same way.

Team Icarus (Canard)

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A canard is an airplane with its tail ahead of the wing. This airplane made a great flight! It flew amazing, and quite stable as well. You don’t see it in the video, because the cameraman accidentally stopped shooting early, but it actually made a safe landing… similar to the conventional airplane, except the landing gear for their plane broke off. (The landing gear failure is actually really common, so most teams expected it to happen… once it breaks, just super-glue it back on). They never got a good second run in though, because of the landing gear failure. They tried, but it just couldn’t take off before the end of the runway, and their landing gear wasn’t good enough to support it.

Team X-Wing (Flying Wing)

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Aesthetically, this plane blew everyone else’s away. Structurally as well actually, because they had a very thick spar with super thick ribs supporting the entire plane. They definitely did an excellent manufacturing job. In fact, their plane crashed and survived the most times, which was amazing. The only problem was getting it up in the air! It was so heavy (because of the structure, which our group decided to not care about) that it had a lot of trouble taking off. Their best flight came on a hand-launched flight.

And to give you an idea of what I’m talking about, most of their flights looked like this.

Team Phabzz (Bi-Plane)

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I called this the “true engineering work of art” because it was almost completely constructed of foam and duct tape. Everyone knows that duct tape is what true engineers use! Their plane was not designed to fly with their landing gear; the wheels just support it for the take-off and they land on the fuselage (you can see it clearly in the video). They managed to take off, but because of a dynamic stability problem, the airplane just kept oscillating in pitch, until it finally crashed. On their second flight attempt, the wing clipped the landing gear as it tried to take off, and it fell apart.

After seeing a bunch of flights (and crashes), I think one of the funniest moments for me was watching our plane crash on the roof. And the fact that everyone just stood there. With the other flights, whether it was a crash or a successful landing, people just ran over to the airplane and they were all super excited. When my group crashed, it was literally an awkward crowd of “oh, what do we do now?

So there are all the teams from our flyoff! It was a great day. The weather was nice, and in general I had a lot of fun watching these planes fly. This course was one of the most stressful courses… but in terms of reward-to-stress ratio, it was also definitely the highest. Given the choice, I’d still do it all over again:)

One response to “Design Debrief

  1. Pingback: Twenty-fifteen | Adventures of a Wandering Flower·

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