up-apr8b.htm Small-Pogo Project


Small-Pogo Project


Status Updates


April 18-30, 1998

April 18, 1998

Busy day. I ran the vehicle on the ground without tethers. I had hoped to be able to hop it up and down a little, sort of a mini-free flight. Instead of lifting off it toppled over as I was bringing the power up. There was slight damage to the bottom of the shroud but it's easily repairable. I learned:

I bought a camcorder. It's a Sony and has 16X lens magnification and 64X digital. I did not get the one with image stabilization because of the extra cost.

I picked up a leaf blower to see if it could be used for powering vehicles. Here's what I found:

April 22, 1998

Yesterday I helped a friend with his jet engine project. We started cutting metal on the lathe. Most of the time was taken up cleaning up the attachments (some had been in a box for 25 years) and learning which tools worked best for what. After 3 1/2 hours we had cut a 1" long part. However, this part had several steps, a tapped hole in the center, cut threads at one end, and was made of high tensile stainless. The second one will probably take 45 minutes and, if were were going to build one, the third in about 1/2 hour. There was a lot of learning.

Tonight I reshaped the landing legs for better stability. I'm going to pick up some balloons to act as air bags should the vehicle fall over again. I still need to stiffen the center body and add the trim tabs. Here's hoping for another run this weekend. I never realized before just how much work has to be done around the place in the spring.

April 25, 1998

Today I repaired the crack in shroud, started rewiring and replumbing so I can stiffen the center body, and building the upper stage mount. Friday I picked up a lazy susan so I can test rotation. I also picked up some balloons that are labeled as being 5' long. They seem to be relatively thick and one of them even has aliens printed on it. I'll wrap these around the vehicle like an inner tube for protection.

April 27, 1998

Good progress today, sort of. I spoke with a model helicopter flyer about the stability of helicopters. They are somewhat stable because of the loose coupling with the vehicle body and the gyroscopic force of the rotor. This vehicle should have an equivelant stability because the center of crosswind pressure is above the center of gravity. Therefore, I expect that once it lifts off it will try to translate but will quickly (within 10-20 ft) reach a stable speed of about 7 mph (10 fps). This means that when I first launch it I need about 50-100 ft of open space to learn how to get it under control before it hits something. Once I gain experience I should be able to make it hover and land vertically. That first flight is going to be real interesting. I've also admitted to myself that some of the slow progress lately has been due to nervousness about the possibility of a crash and major damage after all that money and time. I'm now over that mental block and am picking up speed again.

I attached the upper tie-downs which will be used for attaching the upper body, the parachute, and tethers, if need be. I mounted the bulkheads inside the upper center body tube.

While inspecting the lower center body (where the fuel tank and avionics are) I realized that there were too many cracks, too much fuel soaking, and such to salvage it. Therefore I cut it all off. I don't expect rebuilding to take more than a few days and when I'm finished it will be more structurally sound and modular. I was going to have to stiffen it anyway and this will take only a little more time. A step back to take two steps forward.

The last few days I've been collecting model airplane engine data on weight, thrust, horsepower, cost, and etc. In plotting this data I found that there is a relatively straight line for hp/wt, wt/cc, and hp/cost. There is only a poor correlation on hp/cc and insufficient data on thrust/cc, though there may be two curves (possibly two different types of engines). Further analysis will have to wait for a few days.

April 30, 1998

Started building the new lower center body. Rough cut the bulkheads. Added the nut plates to the upper center body.

Found another source of television camera/transmitter/receivers. Supercircuits. Check out the 2.4 GHz ATV FM Video Link.



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