Brief:
The Semroc cc:X-21 is a boost glider with an elastic cord that pulls the elevons up to shift into glide mode after the motor is ejected.

Construction:
The kit inlcudes 1 body tube with a clear payload section and a balsa nosecone. This is a glider with broad swept wings. There is an elastic cord that pulls the elevons up but you also have a stiff string that is anchored in between the motor mount and motor with a pin. When the motor ejects, the pin is released and the elastic pulls the elevons into position. The elevon position is set by two metal pins that are glued to the wing and are bent into position.

You leave the nose cone friction fit to the payload section so you can adjust the nose weight. The nose weight is supplied with the kit.

The instructions are downloaded from the internet. They are a scanned copy in .PDF format. It isn't the clearest scan and there are lots of bulsa parts with some of them lookin very similar to each pther. On one hand I would say the instructions were not very clear, but after reading them quite a few times as I went through the steps, I was able to put the kit together without any mistakes. It really was an enjoyable build as it was somewhat challenging to figure out how all the parts go together. In the end, it really isn't hard to put together.

The pictures on the Semroc site do not do this rocket justice. It is much bigger and has some interesting wing angles. It also comes with parts to make a jig that holds the body tube as you are gluing the wings together and then joining them to the main body tube. There is a clear payload section too.

Finishing:
The balsa components are laser cut. It is somewhat difficult to finish because of all the parts that are used to assemble it, but the kit is a good one and the quality is there. It is very light so you have to be careful not to break anything when finishing. I accidentally broke one of the balsa elevon stops but a little CA took care of that. I used wood glue throughout the build otherwise.

Construction Rating: 5 out of 5

Flight:
I wanted the first flight to be an A8 but I didn't have one. I used a B4. It took off fast and arched over. As it started angling down, the motor ejected. It wasn't very high off the ground so I can't say anything about the glide. I used 2 of the 3 supplied washers for nose weight. I think I am going to add the third washer for the next flight which will be on an A8.

Recovery:
There is no wadding needed as there is no parachute. As the instructions suggested, I used a pin with the supplied string to hold the elevons down until motor ejection. This worked very well for me. I did glue the pin to the string so that the pin would not free fall after ejection. I only gave it a 3 on recovery but it is because I need to tune the glide. It will take more flights to figure out the best balance between nose weight and elevon angle.

Flight Rating: 3 out of 5

Overall Rating: 4 out of 5