School Project - Help
04-14-2014, 04:28 AM
#103
Yes, now the photos work. I am eager for the final report. I am especially interested in that terrible ground handling task over the roofing. Perhaps it will be easier than I imagine but it seemed a beast of a task.
I hope they shoot some video of the tasks.
I hope they shoot some video of the tasks.
04-14-2014, 06:09 AM
#104
Moderator
We held our aero design contest in Fort Worth a few weeks ago. As usual, there were some teams that really had their acts together and a lot of teams that didn't take it seriously at all and a few teams that had no business even being there. I had to give a Canadian a good talking to after he came barreling into our crowded parking lot where some small children were playing. It was the day before the contest, and they felt like their plane should get its first test flight before the judges saw it. Note I said first test flight, as in never even started the motor before that day. Apparently, they weren't finished building the plane yet either so they missed the opportunity to do their trim and test flight in our Texas 20 mph winds. Their plane performed predictably.
I had a very pleasant conversation with a Mexican from Baja who was an absolute sponge for aeromodeling information. His team did ok and brought their plane home in roughly the same condition in which it arrived. Another team in micro class covered their entire airframe with carbon fiber. It was a good thing too, because their first two flights (hand launched) began with them not realizing that their prop was spinning backwards. Notice I said they made that mistake twice. There was no damage in either nose in crash, so they fixed it for the third and final attempt. It didn't make much difference.
Lots of planes in regular class failed to take off or had lots of trouble because of poorly designed landing gears. It was fun predicting which ones would make good flights and which ones would crash before reaching the end of the runway. I got surprised a few times; I'd say my predicting record was around 50%.
So with it fresh on my mind, I'll offer a couple of last minute tips for your team Petkov. 1. If you haven't already, contact the club where the contest will be and ask about the typical flying conditions. Any member of my club would tell you that it's usually windy, so planes with huge wings that are designed to float don't usually do well there. Knowing the typical density altitude range will be helpful in choosing props for you. 2. Work on making well balanced coordinated turns, because when flying with a load it will mean the difference between losing a little altitude through the turn versus spinning the plane into the ground. I saw a nicely designed plane hit the trees the day before the contest because the team's pilot hadn't learned to fly with the rudder and had some really bad adverse yaw due to the wind conditions. It was an easily prevented crash if he had just known what to do. 3. Get to the venue early and check every fastener, connection, servo, control horn, etc. Have spares for everything you could replace on the spot too. I watched a number of planes miss their flights due to some 12 cent fastener missing or a piece that got bumped and broken. 4. Know your plane. Have your pilot do as much test flying as he can so he knows the quirks of your design. That thin airfoil is going to be unforgiving of stalls (at least I think so), so your pilot needs to have an instant recognition of one that is developing. He needs to know how the plane acts in wind and turbulence, and he needs to be able to land it without even thinking much about it.
Good luck in the contest and let us know how it goes.
I had a very pleasant conversation with a Mexican from Baja who was an absolute sponge for aeromodeling information. His team did ok and brought their plane home in roughly the same condition in which it arrived. Another team in micro class covered their entire airframe with carbon fiber. It was a good thing too, because their first two flights (hand launched) began with them not realizing that their prop was spinning backwards. Notice I said they made that mistake twice. There was no damage in either nose in crash, so they fixed it for the third and final attempt. It didn't make much difference.
Lots of planes in regular class failed to take off or had lots of trouble because of poorly designed landing gears. It was fun predicting which ones would make good flights and which ones would crash before reaching the end of the runway. I got surprised a few times; I'd say my predicting record was around 50%.
So with it fresh on my mind, I'll offer a couple of last minute tips for your team Petkov. 1. If you haven't already, contact the club where the contest will be and ask about the typical flying conditions. Any member of my club would tell you that it's usually windy, so planes with huge wings that are designed to float don't usually do well there. Knowing the typical density altitude range will be helpful in choosing props for you. 2. Work on making well balanced coordinated turns, because when flying with a load it will mean the difference between losing a little altitude through the turn versus spinning the plane into the ground. I saw a nicely designed plane hit the trees the day before the contest because the team's pilot hadn't learned to fly with the rudder and had some really bad adverse yaw due to the wind conditions. It was an easily prevented crash if he had just known what to do. 3. Get to the venue early and check every fastener, connection, servo, control horn, etc. Have spares for everything you could replace on the spot too. I watched a number of planes miss their flights due to some 12 cent fastener missing or a piece that got bumped and broken. 4. Know your plane. Have your pilot do as much test flying as he can so he knows the quirks of your design. That thin airfoil is going to be unforgiving of stalls (at least I think so), so your pilot needs to have an instant recognition of one that is developing. He needs to know how the plane acts in wind and turbulence, and he needs to be able to land it without even thinking much about it.
Good luck in the contest and let us know how it goes.
04-14-2014, 07:01 AM
#105
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We do have videos of the test flights but I am having trouble locating the files. Will post soon.
The team completed the tech inspection and performed flawlessly on the taxi run. They are returning today, so I await to see how the rest of the missions have gone.
Weather was quite windy past few days in Wichita, with gusts of 35+ mph. I am really hopeful that wind did not adversely affect the plane.
The team completed the tech inspection and performed flawlessly on the taxi run. They are returning today, so I await to see how the rest of the missions have gone.
Weather was quite windy past few days in Wichita, with gusts of 35+ mph. I am really hopeful that wind did not adversely affect the plane.
04-14-2014, 07:14 AM
#106
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jester - some of those stories relate to the DBF team the first year that i joined. I had little knowledge of the project and joined late. At first the plane seemed fine and really sturdy. It had be build almost entirely out of carbonfiber and aluminum . When we flew to Kansas I realized that the rest of the teams had completed many test flights and had really light airplanes compared to our 9lb plane which had not been tested once.
We tested the plane at an airfield the day before competition and learned that the static thrust we got in the lab from the motor did not fair well when the plane began move. Right after take off, the plane smashed into the ground and although undamaged, it became apparent that it would not fly at missions.
here is a picture of the beast:
We tested the plane at an airfield the day before competition and learned that the static thrust we got in the lab from the motor did not fair well when the plane began move. Right after take off, the plane smashed into the ground and although undamaged, it became apparent that it would not fly at missions.
here is a picture of the beast:
04-14-2014, 07:37 AM
#107
We do have videos of the test flights but I am having trouble locating the files. Will post soon.
The team completed the tech inspection and performed flawlessly on the taxi run. They are returning today, so I await to see how the rest of the missions have gone.
Weather was quite windy past few days in Wichita, with gusts of 35+ mph. I am really hopeful that wind did not adversely affect the plane.
The team completed the tech inspection and performed flawlessly on the taxi run. They are returning today, so I await to see how the rest of the missions have gone.
Weather was quite windy past few days in Wichita, with gusts of 35+ mph. I am really hopeful that wind did not adversely affect the plane.
35 mph gusts are pretty difficult for flying. Just completing the tasks in that kind of wind is an accomplishment. I hope it was straight down the runway. 35 mph cross winds can flip most RC planes.
Last edited by aeajr; 04-14-2014 at 07:39 AM.
