Category Archives: Uncategorized

The Boneyard: Cessna Field

Most of the photographs (Courtesy of our dashing cameraman Erik!) we have posted so far are close ups of the plane and the build team. But he has also captured some striking imagery of the backlot areas of Cessna Field.

These didn’t fit in anywhere else, so I decided to leave them here. The best description I can come up with is “beautifully post-apocalyptic.” Enjoy, and click on the pictures for gorgeous full resolution!

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Do Not Talk About Flight Club

No word on which one of us is Tyler Durden.

Today we have to do something unusual. We have to prevent our plane from taking off! The mission is to roll along a corrugated sheet analogous to a dirt runway. We have to maneuver around a few obstacles, but the plane has to remain grounded! This is trickier than it sounds, as the plane is driven by the propeller and must have the wings attached for this test. We had to balance a short take off distance (there is a minimum requirement for later missions) with the ability to taxi without liftoff.

We should be called for the mission soon after the competition managers finish setting up. It’s a little chilly out here but it will only get hotter as the day goes on.

The plane has no issues (nothing has gone wrong because nothing has happened yet) so we are anticipating a good run. Our wheels fit almost exactly between the corrugated sheet ridges, which does make it difficult to accelerate over them. However, there is a plywood “on ramp” we start on, to gain up speed. We have easily cleared the sheet in practice runs using a similar tactic.

Since the taxi mission has little chance of damaging the plane (except now I’ve cursed us by saying that) we should ideally get to fly today as well.

I will provide updates here until we start flying, then link to the next post! (Three guesses what the next title is.)

UPDATE:

0930: Did we complete our taxi mission? It’s vitally important, as it acts as a multiplier for the rest if our score. Read on, out loud and in your best dramatic voice.

It was a chilly, overcast, and blustery morning at Cessna Field. Sustained 20 MPH winds buffeted planes and flight crews on the ground, and gusts swatted unlucky planes from the air during their flights. Our task was simple, roll along a corrugated sheet, around two barriers made from lumber.

In calm conditions, our plane had been more than up to the challenge. But when our number came up, we were allotted five minutes. Three hundred seconds, breeze or gale.

On each attempt, the wind howled across our wings, driving the plane back or sweeping it out of bounds. We didn’t dare keep the propeller on full throttle for fear of taking off and failing the mission.

Tick. Two minutes.

Success? The plane navigated both obstacles, but a gust kicked the rear landing gear just off the edge of the track as it crossed the finish line. We looked to the judge. “Sorry.” He said simply.

Tock. One minute.

A scramble to recover the plane and reset it at the beginning again. A reckless drive for the finish, like something from the Dukes of Hazzard, during a lull.

One last gust, throwing the rear wheel into a collision with the final obstacle. It bent, now useless, but the plane would not be denied. A desperate lunge for the finish before time out or the wind returned, the propeller screaming as it dragged its mangled landing gear…

…over the line! A successful end to a nerve wracking ordeal.

Summary: They see us rollin’, they hatin’.

Gonna Fly Now

We made an inspirational montage as we prepared the plane for the flight mission. Unfortunately it consists of one clip, us straightening out the mangled rear landing gear.

We will have to—

BREAKING NEWS MID POST UPDATE

This plane arrived to deliver the news.
This plane arrived to deliver the news.

Our number came up again so quickly that I didn’t even have time to finish writing before we went to the first flight mission. Please put on your best dramatic reading voice again:

Late morning. The sun had scorched away most of the clouds, but the wind remained. Its temper had settled, and the gusts were less frequent and less intense.

But, while our cargo bay was full for the taxi mission, we had to fly unloaded here. The plane needed to survive four minutes in the air, and reclaim the earth on its own terms, without crashing.

But first we needed to take off. We switched propellers and tweaked our electronics, upping our power output to a startling 450 Watts.

It almost wasn’t enough. Stiff wind blew us into the air as much as we flew forward to take off. Thirty pulse pounding seconds later, the plane clawed through the wind to the first flag.

Going the other way was easy; we couldn’t slow down with such a strong tail wind, even if we wanted to. This process repeated, a struggle one way and a reckless sprint the other.

Four minutes elapsed, time to land. The terrifying part. We turned into the wind one more time, slowing until the plane almost hovered. It drifted down to earth, looking almost graceful. But all the way, it was on the verge of being blown backwards and tumbling to a crash.

Finally, the wheels touched down. Bump, bounce, skid. Two laps, no damage. Lighter, less powerful planes were not so fortunate. But we returned, victorious.

Not to mention FABULOUS.
Not to mention FABULOUS.
Our adoring public.
Our adoring public.

All There Is To Know About the Flying Game

Staying in the air is important for airplanes.*

*Citation needed.

However, the most important part of being an airplane is making a successful landing, with as few explosions as possible. This way, you can continue being an airplane. Last year, our electrical problems played havoc with our attempted landings, causing serious damage to the plane each day. This year, we rely on first-string electronics (we ended up using backups last year) and our good karma to prevent such issues.

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“Struggling” to hold back the plane as the propeller spins at 0 RPM.

UPDATES:

Waiting... watching...
Waiting… watching…

0945: We are preparing our plane for technical inspection. The judges check to be sure we have appropriate failsafes (fuses) and that our plane is airworthy. Both are prerequisites for being cleared to try the main missions.

1010: One of our battery packs is mysteriously low on charge! Dedicated readers remember that we just charged last night. Is it leaking?

In the short term, we will attempt two fixes. We will of course recharge. Also, we will disable the low voltage cutoff on the speed controller. Normally, the plane would shut down when the batteries get too low. We can easily override this behavior, to continue flying to the last joule.

We haven’t even been cleared to fly yet and we’re already disabling safety features. Welcome to engineering, check your common sense at the door.

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A full house!

1058: The team is hard at work playing cards while we await technical inspection. There are teams from all over the US, both coasts and everywhere in between, not to mention the international teams!

They have us sheltered in a hangar while we wait, protected from today’s vibrant sun. It’s great flying weather, but my Irish complexion is thankful to be in the shade instead.

Work hard, play hard.
Work hard, play hard.
Hanging around the hangar.
Hanging around the hangar.

1135: Batteries charged, and we are producing over 50 Watts/lb! Not too bad.

1202: 18 teams left until they call our number. Also, Mitchell says “I am a frisbee elitist.” I refuse to provide context for that quote on the grounds that it’s funnier without any.

1315: Did you know there are crucial differences between types of shrink wrap? Now you do! And knowing is half the battle! The other half, in our case, is struggling to resolve our battery issues before inspection. We are team 43 and they are on 31 now.

Drama! Thrills! Suspense! Keep mashing the refresh button until I update again, obviously.

1515: Bureaucracy, my old nemesis…

Our plane passes tech inspection, but we aren’t allowed to fly until we fill out the pre-tech inspection form… after tech inspection. Yes, you read that right.

Unfortunately this means we missed our first chance to do the ground taxi mission, but we will get another chance when our number next rolls around. The form has been taken care of!

1645: SOUND THE BELLS, WE ARE CLEARED! The plane passed tech inspection with flying (heh) colors. We will begin our ground test next time our number comes up. I will have a few more updates today re:how the test goes and any subsequent repairs.

1945: Our number never came up! Fortunately we should be just about first in line in the morning.

Tomorrow will come in a separate post. I hope you will be entertained by my slow descent into madness. Hopefully we will also be able to provide you with more pictures of the airfield–there are a lot of experimental planes and cool scrap parts around!

The road to the runway.
The road to the runway.

Handle With Care

Xavier disapproves.

DISASTER!?! Just kidding. Our plane suffered some minor damage from shipping. There is a crack in the tail, a break in the cargo bay top, and various scuffs and scratches. Nothing too serious, but it needs to be taken care of to prevent further damage. We especially need to be sure all of our electronics are in order, as last year our plane suffered from electrical problems. The batteries were too powerful, overloading the speed controller (which regulates power to the propellers), causing overheating and several spectacular unfortunate crashes.

Charged with anticipation.
Charged with anticipation.

We are also taking inventory of all of our tools, spare parts, and backup components. This is so, when everything inevitably goes horribly wrong, we will be able to quickly recover. Other preparations include scouting out driving routes, charging batteries, and spamming this blog with updates for you, dear reader.

 

Speaking of our burgeoning social media empire, I should give a shout out to our Twitter account, run by my esteemed colleague Mitchell. For those of you hanging on the edge of your seats, he should be able to provide you with more frequent updates than I can.

Can we repair the plane in time? Will we eat Chipotle again? Check back tomorrow for more hard-hitting aeronautical journalism!

Wichitalking ’bout Willis?

My sincerest apologies for the terrible pun. They will only get worse as the weekend progresses. We have arrived! The weather was excellent for flying both legs of the journey, and we have confirmed that our plane arrived to Wichita intact. This is crucial, because having a plane is integral to participating in an airplane competition.*

*Citation needed.

We experienced some minor turbulence en route, and in keeping with our new educational theme, I would like to explain that phenomenon.

Turbulent wake.
Turbulent wake.

In general, turbulent flow is the motion of a fluid (air, water, or whatever) that is chaotic and unpredictable. Pressure and velocity are highly variable within turbulent areas. Turbulence is, to simplify things, caused when the oncoming flow is moving fast enough that it scatters and disperses from its original, laminar pattern.

Not everyone knows it, but the external flow around airplanes is actually already turbulent! Laminar flow is “tripped” into turbulence by the plane slicing through the air. This is actually a good thing, because turbulent flow “tumbles” along the wing for a greater distance before separating. Picture a large semi truck, and the lull of air behind it. There is a high pressure in the front of the truck (oncoming air) but very low pressure directly behind it, because all of the air has been forced out of the way. For an airplane, the boundary layer separating from the wing can be a major source of drag. Minimizing this pressure drag effect is important, and so turbulent flow is useful for planes, cars, and so on. This is good, because at high speeds and for large objects, turbulence is unavoidable!

Designers will even go out of their way to induce turbulence! Golf balls are a clear example. A smooth sphere the size of a golf ball, hit by a human golfer, will not cause turbulent flow and hence the boundary layer will slip off quite early. (Clark Kent might be able to induce turbulent flow with a golf swing, but he can also fly backwards around the Earth to turn back time if he wants.) A rougher surface, like a golf ball with dimples, induces turbulent flow and a boundary layer that does not separate as early, greatly reducing pressure drag.

Texas Hold ‘Em

More accurately, Texas Hold Us. We have arived in Dallas and are awaiting our transfer to Wichita. Updates soon to follow. For now, some shameless rumor mongering about next year.

Currently, we focus on design meeetings (once a week) and build time. We would like to add more theory to our lineup. This will entail computer aided design tutorials, case studies of famous or influential aircraft  and some fancypants aerodynamics math.

After the competition, we are going to have some meetings to work out our syllabus. Exciting! In the coming posts, I will try to add some educational value by talking more in depth about the parts we inevitably end up repairing.

AIAA Weekly Update #8: Pretty Fly

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The majestic model airplane, in its natural habitat.

IT’S ALIVE! After finishing with our indoor testing last week, we absconded to the park with our plane for some aerial amusement. Our maiden voyage was successful, with the plane taking off in good weather and zipping to and fro like it was made to fly. Probably because it was.

The results were certainly encouraging. We know that the plane can carry the necessary cargo, taxii across a rough surface, take off within the necessary distance, and even land without breaking (much)!

The plane has since been shipped to Wichita, Kansas for the competition! Our team will board a much larger plane to follow it there, on Thursday afternoon! The competition will take place from Friday to Sunday.

Expect to be spammed with blog updates in the near future! Also watch our twitter feed, which will be all atwitter with tweets this tweekend.

AIAA Weekly Update #7: Fin!

test2The plane is completed! One of the latest challenges we faced was manipulating the control surfaces. Our flaperons needed to have the ability to act as flaps and ailerons, using only one control stick! Ultimately we found a way to switch the mode between flap and aileron control, on the radio transmitter. Our tail/rudder assembly is also complete!

We are now testing the plane’s capabilities, making spare parts, and preparing for our competition journey! One of our first tests was a dry run of the corrugated sheet taxi mission. The plane must roll along a rough surface without taking off and while avoiding obstacles.

As always, if you are interested in building airplanes and airplane-building-related activities, stop by our weekly meetings on Mondays at 9 PM in 233 Mudd. Also head to the machine shop on the second floor of Mudd on Friday afternoons; we spend most of our build time there.

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AIAA Weekly Update #6: Progress Report

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Testing our new electronics!

We have been busy! Construction of our plane continues, of course. Our electronic parts arrived a while ago, so testing and connecting them is one of our major tasks. Without motors, servos, and the radio receiver, our plane would just be a glider!

Control Surfaces (Thanks to Wikimedia Commons!)

In more interesting news, we are considering how best to make use of our control surfaces. There is of course the rudder, which is connected to our rear landing wheel such that it acts to steer the plane whether it is taxiing or flying. There are the elevators (on the tail) which are raised or lowered together to pitch the plane up or down. And there are the wing control surfaces, known in our case as flaps or ailerons.

On larger planes there are separate flaps and ailerons. Flaps are used together to increase the wing’s coefficient of lift by tilting down, increasing the curvature of the wing. This can help a plane take off and fly safely at low speeds. Ailerons, on the other hand, tilt opposite each other to roll the plane. If the plane wants to roll to the right, it raises the right aileron and lowers the left. Thus, lift on the left wing increases and lift on the right wing decreases, causing the right wing to dip.

However, our plane is using a combined flap+aileron setup, informally known as flaperons. All this means is that our ailerons can be raised and lowered together (as flaps) or separately (as ailerons). This way we can get the benefit of flaps during takeoff and ailerons during flight, without having to add extra servomotors and control surfaces.

As always, if you are interested in building airplanes and airplane-building-related activities, stop by our weekly meetings on Mondays at 9 PM in 233 Mudd. Also head to the machine shop on the second floor of Mudd on Friday afternoons; we spend most of our build time there.