Various Testing Platforms

Scout V 0.4 RPTV (Retro Propulsion Test Vehicle)

Scout V 0.4 RPTV during a static fire.

 

January 13th, 2016

Serving to assess the strength of the Thrust Vector Control system onboard Scout V 0.4, the first RPTV ignited the D10 retro rocket in a static test. The test confirmed that the TVC system, in the retro-propulsive calibration, was strong enough to hold the mount at a zero-position.

 

 

Scout V 0.5 RPTV (Retro Propulsion Test Vehicle)

The moment of dual-motor ignition.

 

February 14th, 2016

Filmed at 240 fps from multiple angles, the Scout V 0.5 RPTV was used to assess ignition timing consistency between both motors used onboard for retro-propulsion. The test proved that the ignition of two APCP motors, using proper ignitor positioning,  could be achieved effectively at the same time, which would be crucial for landing under thrust of both consistently and safely. 

 

RRTV 1 (Retro Rocket Test Vehicle 1)

RRTV1 just after ignition. Note the slightly thicker plume of exhaust on the left burner in the frame.

July 30th, 2016

Retro rocket test vehicle 1 was the first attempt at simplifying the TVC system. By moving more powerful retro-rockets to the top of the vehicle and angling them 30° outwards (axial thrust was solved for using vector resolution) it would seem to be able to stabilize itself. However, this has been proven incorrect by what's known as the rocket pendulum fallacy. The test, while acknowledging the issues presented with the rocket pendulum fallacy, was conducted in order to assess the amount of deviation experienced by the rocket upon ignition of both burners. 

Though the motors ignited relatively closely, time-wise, the ignition cable was caught on one of the onboard cameras, and halted the rocket, mid flight. The rocket tipped over, and the retro-rockets finished burning with the rocket on the ground.

While the test seems inconclusive, the small about of data that was acquired through high speed video was used to assess the initial moments before arrest by the ignition cable. With this data, it was determined that with a small bit of 1-axis planar thrust vectoring, the rocket could remain relatively stable. This lead to the development of the RRTV2.

 

Scout V 0.8 TVTV (Thrust Vector Test Vehicle)

Actuating at ±6.6 degrees on each axis, this test proved the effectiveness and reliability of the new thrust vectoring hardware.

 

August 3rd, 2016

The V 0.8 TVTV was used to prove the electro-mechanical strength of the new TVC motor mount design, after several failures of the previous design. Performing nearly flawlessly, the design used roughly half the space and half the weight of the previous vectoring system, placing both actuation servos on the sides of the booster instead of the top.

 

 

RRTV2 (Retro Rocket Test Vehicle 2)

The RRTV2 in mid-spin just after liftoff. While not constrained by an ignition wire, the RRTV2 suffered a similar fate to that of the RRTV1.

 

August 11th, 2016

Though the RRTV2 used active thrust deflection onboard to account for deviations in ignition time and strength of each retro-burner, the deflectors actually induced roll to the vehicle, ultimately destabilizing the flight, and bringing the rocket to the ground within seconds. The RRTV2 was the second and final of it's series, proving the futility of moving the retro-propulsive motors to the top of the vehicle, as they would still need to be fully vectored. This is demonstrated by the Rocket Pendulum Fallacy.