Flight Log - 2022-07-26 - John Simmons's (BAR-10) The Cygnus Probe Ship

A flying model rocket based on The Cygnus Probe Ship from the movie The Black Hole.

This rocket is mostly made from pine components turned on my wood lathe.

It is powered by a 29mm motor.

Getting the rocket to be stable has been quite a journey.  It swing tests as stable, yet if you check out the flight reports, it flies stable under thrust, but then tumbles during the coast phase.

I've built and swing tested the rocket using an extension for the BT-55 main body section.  I have yet to launch it with this new configuration.

Link to Build Thread.

Flight Date: 2022-07-26
Rocket Name: (BAR-10) The Cygnus Probe Ship
Flyer's Name: John Simmons
Motors: F42-4
Expected Altitude: 388.00 Feet
Wind Speed: 5.00 mph
Launch Site: Local
Actual Altitude: 388.00 Feet

Ignition was delayed, slight hesitation as is typical with a composite motor.

The rocket accelerated quickly, plenty of speed at launch rod exit (28.2 mph per sim)

Winds were less than 5 mph and from the west. The rocket did not weathercock.

Just like the 1st flight, the rocket was initially stable while under thrust, but was not stable during the cost phase. It tumbled end over end.

The simulation software estimated apogee @ 388 feet, but the rocket did not reach that height due to the tumbling during the coast phase (no altimeter was used).

Visually as the rocket descended, the chute was fully deployed.

The rocket ground hit south of the launch horse. Photo's were taken of the rocket at it's ground hit location. Upon further review the rocket was undamaged except for a fracture of one of the wooden legs which was easily repaired at a later date.

What was learned from this flight?

Even though this rocket swing tested as marginally stable, it is not stable.

The base drag hack used in Open Rocket isn't applicable to this rocket since it has a tail cone design. Don’t use the base drag hack if the rocket has any sort of tail cone.

I have since built an extension for the upper body tube to make the rocket stable. I hope to launch this rocket again and get a good stable flight.

StageMotor(s)
1Aerotech F42T-4

 

comment Post a Comment