Aerotech Astrobee-D

Aerotech - Astrobee D {Kit} (89015) [1989-]

Contributed by Ken Bracey

Construction Rating: starstarstarstar_borderstar_border
Flight Rating: starstarstarstarstar_border
Overall Rating: starstarstarstarstar_border
Manufacturer: Aerotech
Style: Sport

Aerotech Astrobee D Brief:
The Aerotech Astrobee D Kit is one of the tallest Aerotech Mid power kits. It is a scale replica designed to fly on F and G motors. The rocket separates at the middle and both sections recover separately on their own chute. The kit comes complete with detailed plans of the actual Astrobee 'D' and the usual Aerotech features such as ejection cooling mesh and a no-wadding-required baffle system.

Construction:
The kit parts include 2 2.6 inch body tubes, a motor mount tube, thrust ring and motor hook, 4 plastic molded fins and Aerotech's Fin Lok system with thru the tube fin mounting. A tube coupler and bulk head assembly, plastic nose cone, a 22 and a 30 inch yellow nylon chute with plenty of elastic shock cord and 2 screw eyes. Detailed instructions are also included with paper layout templates for positioning important scale parts. 1 decal sheet is included. Various miscellaneous other items for completing the scale rocket such as scale launch lugs and scale antennae are included.

Pros: Impressive looking rocket (it is almost half scale). Instructions were straight forward. The layout templates were handy for positioning some items. The fin mounting system assembles with a positive 'click' into position. It is almost impossible not to get the fins on straight and in the correct position with this system if the instructions are followed. The cooling mesh and baffle system is easy to assemble and works well.

Cons: The tube coupler with this kit was extremely tight and I had to remove the first layer of paper from it and then sand it even more before I could get the fit right. I was so concerned with the tight fit of the tube coupler at first, that I even called Aerotech to make sure that I had the right piece. They told me that sometimes different humidity conditions can make some pieces swell in size! Before painting the fins, the instructions tell you to apply the fin boot decals to the leading edge of the fins. These decals are clear in color and the decals with this kit are a bit thick. The instructions call for you to cut out the decals and then fold them in half to make applying them to the leading edge of the fins easier. I found that putting these decals on was extremely difficult and ended up getting creases and bubbles under the decals that I just could not get out. I also did not understand the reasoning behind putting on the decals and then painting over them. After an E-mail to Aerotech again, they informed me that the purpose behind the decals was to give a bit of thickness to the leading edge of the fin to provide the appearance of the fin boots on the real rocket. I decided that I didn't need that level of scale appearance on my rocket since the creases and bubbles in the decal ruined the effect anyway and I removed the decals after having already started the paint job on the fins. By doing this, it left a perfectly straight ridge right where the fin boots would be which provided the perfect scale look of the fin boots anyway Lastly, after final construction was complete I noticed that the nose cone had a very slight warp to it. Once I noticed it became very annoying. I decided that since the rocket was already completed and painted that I would not replace the nose cone and hoped that others would not notice. However, other people have noticed that warp so it was worse than I thought. I may still try to replace the warped nose cone. If I had noticed it sooner, I would have asked Aerotech for a replacement under their warranty at that time.

Finishing:
Pros: Paint scheme is easy for beginners to master. No tricks needed here. The builder has 2 choices of finishing, Launch configuration which has the upper launch band in place or flight configuration which shows the band of bolts on the payload section where the upper launch band was covering.

Cons: Decals are extra thick and don't look very good unless special care is taken with them and then using clear coating to make the decals blend in well.

Construction Rating: 3 out of 5

Flight:
The model has only had one flight so far but that flight was a very nice one. Of course being an Aerotech kit, no wadding is needed with their cooling mesh/baffle system. The single use Aerotech engine fits perfectly in the motor mount which has a forward thrust ring and an engine hook for retention. I used a small piece of wire to tie the engine hook around the motor just to be safe that the motor did not eject (I recommend this with all motors E size and up that use and engine hook!)

The instructions are very explicit on how to pack chutes since this model comes down in two sections with 2 chutes. Each chute is attached to the end of a long piece of shock cord. One shock cord attaches to the baffle on top of the engine mount while the other mounts to the bulk head on the nose cone/upper section. The instructions say that the upper section chute must be packed into the lower body tube first and then the lower body chute must be packed on top of the upper section chute. This is to ensure that both chutes will be ejected and not left inside the body tube. I packed the chutes as instructed and removed the removable antenna before launch (so they don't get broken during the flight!).

The thrust was provide by an Aerotech SU G40-4W motor. Ignition was almost immediate and the Astrobee launched very slowly. It looked and sounded extremely realistic. WRASP simulations predicted about 1350 feet and I estimate that I got about that altitude. It was an almost perfectly straight boost with a nice white smoke trial. Ejection came just before apogee and both chutes appeared within seconds. There was a steady breeze at altitude and the two sections started to drift but did not get caught up in any thermals or such. Both sections landed within 10 feet of each other about 250 meters from the launch pad (a short hike through the bush!!). This flight was one of the most impressive I have ever seen with a mid-sized rocket! The two sections descending side by side was almost as impressive as the boost!

Recovery:
Pros: Both sections recovered within close proximity of each other. Both sections descend at exactly the same rate. Impressive to watch.

Cons: Must pay extra special attention when packing the chutes because proper recovery requires proper chute packing and this takes a bit more time to pack correctly. There is a good chance that the two sections may actually entangle with each other at ejection, hence the special care required in prepping!

I took off half a mark for the flight/recovery rating because of the anxiety I felt thinking that the two sections would entangle with each other at ejection. I feel that there might be a way to engineer something to prevent an entanglement (even though I did not experience and entanglement) but I do not know how.

Flight Rating: 4 1/2 out of 5

Summary:
I feel this kit was very good. I had fun building and flying it. It is an impressive looking kit both standing still and in the air. I was a bit disappointed with the tight fitting coupler and with the warped nose cone but having dealt with Aerotech customer service in the past I know that these problems are easily rectified and should not be reasons to prevent anyone from trying this kit. If you like scale rockets and nice realistic looking flights then I do recommend this kit.

Overall Rating: 4 out of 5


 

Flights

Comments:

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S.R. (January 1, 2001)
The Astrobee D is the whole reason I got back into model rocketry. Big, scale versions of actual rockets that look real taking off. This kit is Aerotech's best by far. It's big and loud, beats the hell out of those dinky Estes rockets I had back in the 70's.
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J.C. (October 1, 2001)
Is is a well built kit. The final rocket is big and beautiful and the supplied decals add the finishing touches. The supplied paint and decal info is very helpful. The only thing you must watch out for is to follow the chute packing directions exactly. The top chute goes in first then the bottom chute.
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L.S.Z. (November 30, 2001)
I built mine for a level 1 attempt on an H128W-10. I modified the kit by leaving out the retainer hook and beefed up the aft Centering ring with .25 plywood. Positive retention and it flew great to 1875 feet. Nxt it will be modified for dual deployment.
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G.A.D. (September 30, 2002)
The tube coupler for the main body tubes is very tight fitting, as is typical for Aerotech kits. This is a problem for the lower tube as this connection must separate in flight. I sanded away a considerable amount of the coupler where it protrudes from the upper section, and then applied a light coat of sandible primer, which I then sanded smooth. This gave me a fit that was snug but which slid apart smoothly. Took a lot of work and care, to get it right. As it is I think I need to do more. On the first flight (on a G35-4) the boost was straight and high, and the two halves separated near apogee, but the momentum of the top portion was expended sliding off the coupler, and it did not pull the chutes out. Eventually the falling sections pulled out the chutes and, after a nervous few moments, everything opened up and the flight ended well. Still, the separation and deployment of the dual chutes is the tricky part of this kit. Still, it's a mighty impressive flyer and looks great once the chutes are open.

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