The flight trajectory was as expected and the RC system worked well. The new RC pilot was a little shaky on the controls but managed to keep the rocket from flying into the tree line and created a very low altitude stalled landing into the grass avoiding any structural damage to the vehicle.
The rocket plane is safely back in the workshop for post flight analysis.
Blue Dart Delta II experimental flight at Crooked Creek to confirm stability of the design and adequate motor sizing prior to commencing the Blue Dart Delta II rocket glider test program. This launch was successful and we’re ready to move on to the next phase of testing with the RC version.
The Blue Dart Delta II is a fiberglass rocket plane. It will launch on a G80-7T Rocket Motor. This is the 2nd Delta II constructed. The initial build was a rocket glider version whereas this one lands like a typical rocket using a parachute. Both will gather flight data to aid in Blue Dart Delta III design refinement.
Delta wing area is 1,428cm2
Tracing the wings, winglets, landing pad, and vertical stabilizer onto 1/4″ thick foam.
Assembled the motor mount including a retainer. Trial fit with a used 29mm G motor.
A layer of BID cloth was cut at 45deg to fit over the 1/4″ foam, then a piece of peel ply was cut to cover the layup.
A batch of expoxy was mixed along with a small batch of micro.
Glassed the first side of the wings, winglets, vertical stabilizer, and landing pad with one layer of BID cloth. The layup was covered with peel ply so the parts come out smooth after cure.
Removed the peel ply and trimmed the edges.
Glassed the 2nd side of the Blue Dart Delta II wings, winglets, vertical stabilizer, and landing pad. Covered the layup with peel ply.
Blue Dart Delta II components start to take shape.
Installed an eye bolt in the front section of the motor mount as an anchor point for the shock cord.
Glassing the body tube with one layer of BID cloth and covering it with peel ply.
Removed the peel ply, trimmed the ends, and sanded the body tube.
Secured the shock cord to the eye bolt on the engine mount and stuffed the cord inside the engine mount.
Marked the installation locations for the rail buttons, wings, winglets, vertical stabilizer, and landing pad.
Installed the rail buttons and the motor mount.
Tacking the components onto the body tube and adding epoxy fillets.
Priming and painting.
Install parachute and attach shock cord to the nose cone.
This Black Brant II is a 2.6″ diameter fiberglass rocket and it is 52.25″ long. It will fly on both G (G67R-14A (38/120) RELOAD. 110NS/1.4SEC) and H (H148R -14A (38/240) RELOAD. 206NS/1.6SEC) solid rocket motors.
Sanded the OD of the motor tube and ID of the centering rings so that the rings fit over the motor tube. Sanded the ID of the body tube and the OD of the centering rings so that the centering rings fit in the body tube. Marked the 3.25” location from the aft end of the motor tube and the 0.5” location from the forward end of the motor tube.
Used 5-min epoxy to secure the centering rings in position.
Used JB weld to secure the 38mm aluminum retainer to the aft end of the motor mount.
Located the positions for the rail buttons.
Sanded the sides of the fins and the leading edges.
Secured the eye bolt to the engine mount and attached the shock cord.
Installed the motor mount and tailcone in the aft end of the body tube.
Installed the three fins onto the aft end of the rocket using 5-min epoxy.
Cut the fiberglass cloth into six 3″ long pieces.
Mixed a small batch of epoxy to wet out the cloth. The cloth was applied to the gaps between the fins and the tailcone.
Applied epoxy fillets to both sides of each fin in front of the glass tape reinforcements.
Sanded the fiberglass strip edges smooth.
Installed the rail buttons.
Verified the CofG was acceptable with the rocket engine loaded (weight simulated) and the parachute and instrumentation onboard. Permanently installed the nose cone bulkplate.