All posts by Kyle Doyle

Wichitalking ’bout Willis?

April 10, 2014UncategorizedBLOGSPAM2014Kyle Doyle

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.

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

April 10, 2014UncategorizedBLOGSPAM2014Kyle Doyle

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

April 8, 2014UncategorizedKyle Doyle

flight2 — 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!

April 1, 2014UncategorizedKyle Doyle

The 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.

AIAA Weekly Update #6: Progress Report

March 12, 2014UncategorizedKyle Doyle

battery-test — 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.

AIAA Weekly Update #5: Construction Montage

March 3, 2014UncategorizedKyle Doyle

Construction of the competition plane is well underway! The VersaLASER has been our workhorse for this build. The ribs and fuselage sections were created directly from drawings “printed” to this laser cutter. These cuts are extremely precise; we could cut parts out manually, but there would be slight differences between each due to human error.

sub24hr-fuselage — Assembly in 24 hours, or your money back!

The fuselage skeleton is complete, along with the tail. Both were assembled this weekend! All wing ribs have been cut out and are awaiting assembly. The wings will be held together mainly by carbon fiber strips, which have been marked for cutting. Unfortunately, machine shop’s band saw is down for maintenance (a rare event!) so the wings will have to wait until later in the week.

AIAA Weekly Update #4: Some Assembly Required

February 25, 2014UncategorizedKyle Doyle

Sound the bells; the report is complete! At a hilarious 54 pages in length, this document represents the culmination of our efforts so far this year. The report, graded by three separate judges, will be a major part of our contest score. It is also the compiled reference for our final design, and will guide us through constructing the competition plane according to the design choices we have made and the experimental results from our prototype and other tests.

The kit and prototype planes have provided valuable test fodder. We tested the prototype with different wheels, taxiing along the corrugated sheet that we will have to navigate during the competition.

Our final task is to construct and fly the competition plane! All of the parts have arrived and the design is complete. The new motor has been put through its paces on the testing rig, shown to the right.

AIAA Weekly Update #3: Virtual Reality

February 19, 2014UncategorizedKyle Doyle

transit2 — Simulator in transit across Columbia’s beautiful campus.

transit1 — Low Library lit up in honor of
Columbia Engineering’s 150th!

Our Engineering Week demo was a great success! We showed off our flight simulator and a foam kit plane for a few hours on Monday night, in lieu of our regular meeting.

We have also completed construction of our prototype and begun the testing process. All that remains is the finish the report and then build our final design! 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.

AIAA Weekly Update #2: Shipping and Handling

February 13, 2014progress reportsKyle Doyle

We will be exhibiting our flight simulator for the ESC’s Engineering Week on Monday, 2/17 from 6-8 PM in the Lerner Hall “party space”. Stop by to get some virtual flight time in! In fact, we might even have the chance to get in some real flying time too, but that’s a surprise we’ll leave for those who come.

Work on the prototype plane is continuing. Many of the constituent parts and electronics are on their way; we are waiting on them to arrive so we can finish that plane! In the meantime, we are preparing our test equipment. We have created a rig for the motor to see how hard it can pull. We also manufactured two 1 lb blocks for cargo. In addition, we bought a corrugated sheet that matches the one our final plane will have to taxi on for the first mission of the competition. The goal is to test different wheel diameters to try and roll across the sheet without issues.

We are also making progress on the all-important design report! On Friday, we will meet to finish and begin editing it. Finally, we are expecting to finish the redesign of our website soon, including bios of our members!

As always, if you are interested in building airplanes and airplane-building-related activities, stop by our weekly meetings at 9 PM in 233 Mudd.

AIAA Weekly Update #1: Maple Syrup

February 4, 2014progress reportsKyle Doyle

With three weeks left until the design report deadline, progress continues apace!

We recently completed our maple-leaf themed kit plane. The first flight will take place as soon as a suitable location is available. Video is soon to follow!

The kit plane has been a great chance to practice assembling a plane in preparation for our prototype and final design.

Speaking of which, construction of our prototype plane is also under way. We have completed work on the fuselage and will order our electronics this week. Assembly will be finished as soon as they arrive. Our flight simulator is complete as well. We eventually plan to use the simulator to test our radio-control equipment. For now, it is only controlled via keyboard.

Our next major task is to complete the design report. This will involve testing our completed builds and making changes to our final design that will be reflected in the report. Once those changes are finalized and the report is completed, our final build will begin ASAP.