|American Alliance Rocketry
The NB5 Emulator from American Alliance is part of their ongoing "story" of a Pan-American Alliance fighting back after being devastated by aliens. The "NB" of the name stands for "New Beginnings" and it is supposed to be a probe to seed other planets.
Rockets from American Alliance tend to have a "different" look about them. I have several but the only one I built before this was the F2 Avenger, and I have been very happy with its performance. This one caught my attention because of the triple rear ejecting parachutes.
The first step called for in the instructions is the marking of the various tubes. There are 3 BT-5s and a BT-50. The instructions were unclear at the stage. I believe the phrase "opposite end" was used in place of "other side". This led to some confusion until I had read through the entire set a few times.
I also noticed that the BT-50 had a nasty, deep spiral. It serves as the motor tube but will be visible so I decided to go ahead and fill the spirals first off. Using a brush, I applied Elmer's Wood Filler and worked it into the groove with a razor blade. The blade was also used to scrape off the excess. Since this left very little material behind, it did not take long for it to dry and the whole tube was sanded down with #400 sandpaper. The spiral, once so prominent, was now hardly visible.
The instructions include a paper template which has outlines for all of the balsa parts. When cut out, it fits exactly over the balsa stock that was supplied. I taped the templates in place and used a razor knife to cut out the three large fins and the three small ones. The similar fins were stacked and sanded to uniformity then all but the root edges had bevels sanded into them.
The template also included a provision to make a jig from the balsa to insert the thrust ring. I knew from previous experience doing this that I preferred to just use a spent motor casing and this was done. The thrust ring was shoved into place using a casing and was secured with yellow glue.
The small fins were applied evenly spaced and flush against the bottom of the BT-50. A double glue joint was used and, when dry, the fins were filleted using yellow glue. I also used the glue as a "sealer" on the balsa since it would only be slightly visible at the end.
A few hours later, the fillets were dry and I did some rudimentary sanding. The motor tube was then set up in the booth and primed with Kilz. That was given a chance to dry and then the tube was sprayed with a bright red.
When the red paint was dry, I sanded down the outer root edge of the little fins to insure adhesion with the glue. The motor tube and the 2 BT-5 chute tubes were then test fit into the centering rings. The BT-5s fit fine but the center holes needed to be sanded a bit to accommodate the BT-50. When they fit, I took them all apart again and measured 4" and 1-5/8" from the front of the motor tube since the previous marks had been covered by the paint. A razor knife was then used to scrape away the paint where the rings were to go. The pieces were put back together again and aligned to the marks. Care has to be taken to see that the small fins also align with the three BT-5 tubes. Rubber bands came in handy at this point. I glued the rings in place with white glue and applied the first layer of a double glue joint to the bottoms of the BT-5s and small fins. When the first layer had dried, I glued the fins to the BT-5s and used some masking tape to hold everything in place as the glue dried.
As the tubes dried, I applied Elmer's Wood Filler to the large fins. I brushed it on and scraped it flat with a razor blade. About an hour later, I was able to sand them with #400 sandpaper. The result was the nicest set of fins I have prepared to date.
After the glue on the tubes was dry, I tried test fitting the assembly in the upper tube. It would not fit. A fair amount of sanding took care of this. It was still tight and the biggest problem was fitting around the BT-5 tubes but it did go into place. When I was assured of a fit, the lower tube assembly was removed and yellow glue was smeared around the inside of the BT-80. The first of the centering rings was inserted and then some more glue was smeared just inside the big tube. The assembly was then pushed home until the rear centering ring was flush with the end of the BT-80. A long swab was used to apply a fillet around the top of the upper ring.
I tried to test fit the nose cone into the BT-80 upper tube. There was no way it was going to fit. I got out the sandpaper and started taking down the shoulder. I got lots of shavings but it was still way too tight. The next approach was to use the belt sander. That managed to take off quite a bit of material but I eventually got to the point where I was worried about sanding through the base of the cone and stopped, but the fit was still too tight. I took a file and tried to smooth up what had been sanded down. That helped but not enough. My next attack was with #100 sandpaper around the inside of the tube. It was a thick tube, not at all like an Estes tube, and that did seem to help. A little further tweaking on the shoulder of the NC and I was able to finally shove it in. I thought about not gluing it but decided to do so because the base of the cone would bear the brunt of the ejection charge. The NC was pulled out and a ring of tube type plastic cement was put around the inside of the tube and the cone replaced. I don't think that sucker is going anywhere.
The launch lugs were tackled next. The kit has a pair of 1/4" lugs to be mounted on the upper tube. They are to be spaced midway between a pair of the BT-5s and one goes flush against the bottom while the other is placed 3/4" down from the top. I used an angle iron to draw a line and then applied the lugs with yellow glue, using an aluminum rod to keep them aligned.
While waiting for the lugs to dry, I read ahead in the instructions and found that I needed to cut out three shock line covers. These are trapezoidal shaped pieces of balsa used to help secure the shock cord mount. A template for the covers was cut out of the same sheet which had included the fin templates and it was taped onto the balsa stock. An X-Acto and straightedge was then used to cut them out.
The parachutes themselves seemed small but there are three of them. Each consists of a square piece of mylar, 7" on a side. They were assembled by putting a reinforcing ring in each corner and punching holes through the centers. The instructions say to cut 12 pieces of shroud line, each 10" long. Measure carefully. There is no excess. Each of the lines is then tied to the corner of a chute and the other end is tied to a provided snap swivel. If I had been thinking, I would have doubled the shroud lengths and used a loop in the end to make the connection, but I wasn't thinking.
The fins were attached using yellow glue and a double glue joint. Each was checked for alignment with the smaller, inner fin and allowed to stiffen up significantly before the next fin was attempted. They also got several layers of fillets.
If there is one part of this build I am most "iffy" about, its the shock cord mounting. The instructions directed me to make a hole in the BT-5 tubes just above the tops of the fins. I used a drill to do this.
The three lengths of elastic shock cord were then fed down the three holes so that the ends protruded from the aft ends of the tubes. Only a half inch was left sticking through the holes. The instructions then called for the cords to be glued down on the tops of the fins and warned that I might need to hold them for a while as the glue set. I took care of this by using a gel CA.
The shock cord covers built previously from the balsa were then supposed to be mounted over the cord/fin joint. It was readily apparent that I had drilled my hole just a bit to high on the BT-5s and I tried to remedy this by cutting a notch out of the back of the covers. That improved things a bit but its not as perfect as I would have liked. I used CA to secure the shock cord covers and, when dry, I began to try and fair things out with glue fillets.
PROs: This is an innovative design that is different from many other rockets but still goes together fairly easily.
CONs: There are some places where the instructions could be a bit clearer.
I am very glad I decided to paint the central tube red before construction. After making it though, I wish I had gone ahead and painted all the pieces.
The top of the central tube was wrapped with Frog Tape and the tape was used to wrap the bottom of the tube, just above the inner fins. Tape was then used between the fins to mask off the body. I decided to go ahead and redo the inner fins in white since that is what is shown on the face card and because it was easier to mask.
I then used aluminum foil to cover the gaps between the tape and held that down with tape as well. I went over all the tape joints, trying to burnish the edges down with a rounded piece of balsa and then took it to the booth to begin the priming with Kilz.
3 Coats of Kilz were applied. It probably only amounted to 2 regular coats. I realized partway through the first coat that my almost empty can was shooting nothing but aerosols, no pigment, and threw it away. I then let it dry for a while before shooting it again.
When the Kilz was dry, I gave the rocket a light sanding but left it masked. Next up was the gloss white paint. Again, it took 2 coats and is distinguishable from the Kilz only by the glossiness.
The final masking amounted to wrapping the lower section of the rocket with aluminum foil. Then the final painting with a brilliant blue, began on the upper section.
The rocket received 2 coats of blue and I thought it looked pretty good with the masking in place. I made myself wait until the next day to remove the masking. From a distance, it still looked pretty decent.
Closer inspection revealed some problems. There were places where the white had been able to penetrate the masking a mar the underlying red. This needed to be fixed.
I didn't want to re-mask everything so that I could spray it so I used one of my kludge procedures. I took the red spray paint I had used and sprayed some into a paper bowl until I had a puddle. A brush was then used to cover up the worst of the blunders.
The Emulator had a day to dry and then it was time to finish up with the decals. The kit came with 2 waterslide decals printed on a single sheet. They really could have been a single decal but a look at the placement on the face card revealed that the "American Alliance" needed to be cut out and placed separately. The decals were on white backed paper and I would have preferred clear with a white backing under the printing, but I suspect that is much more expensive to produce. In any event, it doesn't look too shabby.
Construction Rating: 3 out of 5
The Estes Ds are the recommended motors for this rocket. I decided to use a D12-5 for the maiden flight. Accordingly, I prepped the motor and loaded it into the business end of the rocket.
The instruction give 2 different methods for loading the chutes. I chose the "triangular" method where wadding is optional. It basically involved folding the chute into a triangle and rolling it up tightly before stuffing it into the deployment tube. The only hard part was stuffing the elastic into the tube ahead of time.
When it came time to launch, the rocket went straight up, even in spite of the high winds. It was a textbook flight and the 5 second delay seemed about right too. It gave the rocket a chance to nose over before deploying the chutes.
All 3 chutes deployed but the high winds promoted a bit of tangling. Even so, the rocket recovered safely and would have been ready to fly again with minimal prepping. Even so, it did not get to fly again this day because of weather concerns and the time it would have taken to straighten out the chutes.
PROs: Good flier and looks cool with unusual recovery system.
If I were to design this kit, I think the biggest thing I would change would be the recovery system mounting. I would probably try to mount the cords in the upper tube and then feed them down into the smaller parachute tubes. That being said, one of the greatest things about this rocket is its uniqueness and the mounting system does contribute to that.
Flight Rating: 4 out of 5
This rocket was at times frustrating during the build but I have really liked it every second of the way. My confidence was found to be well placed when it came time to fly. It just looks great.
The sense of the "different" is something that distinguishes American Alliance. This rocket is no exception.
Overall Rating: 4 out of 5