Excuse Me

Excuse Me 3D frame

Andrew MacMillen's Level 3 Rocket


General information:

  • 12' x 5.5" overall, 14.5" fin span
  • 4-5 calibers stability (2-3 with optional large 98mm solid motors)
  • Ratt M900 hybrid motor
  • 35-40 lbs filled pad weight
  • ~11,000 - 12,500' apogee (dependent on nitrous pressure & wind)
  • Drogue chute near apogee (dual altimeter); ~75 fps descent
  • Main chute at 1000', backup at 800'; ~15 fps descent
  • 6' launch rail (10' rail minus span between upper & lower rail buttons minus hybrid GSE blast plate clearance)

RockSim screenshot:

RockSim screenshot
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Launch plot:

Launch plot
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Flight plot:

Flight plot
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Flight profile:

Flight profile
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Flight profile
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Flight profile
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Flight profile
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Simulation Data:

Engine selection
[Ratt M900H-0]

Launch conditions
Altitude: 2200.000 Ft.
Relative humidity: 70.000 %
Temperature: 70.000 Deg. F
Pressure: 29.921 In. Hg.
Wind speed model: Light (3-7 MPH)
Wind turbulence: Fairly constant speed (0.01)
Wind starts at altitude: 0.000 Ft.
Launch guide angle: -5 Degrees from vertical
Latitude: 48 Degrees north

Launch guide data:
Launch guide length: 72.000 In.
Velocity at launch guide departure: 46.214 ft/s
The launch guide was cleared at : 0.665 Seconds
User specified minimum velocity for stable flight: 43.999 ft/s
Minimum velocity for stable flight reached at: 67.367 In.

Max data values:
Maximum acceleration: Vert: 669.675 Ft./s/s,
                      Horz: 11.219 Ft./s/s,
                      Magnitude: 669.676 Ft./s/s
Maximum velocity: Vert: 948.109 ft/s,
                  Horz: 11.587 ft/s,
                  Magnitude: 974.648 ft/s
Maximum range from launch site: 3917.487 Ft.
Maximum altitude: 11898.389 Ft.

Engine ejection charge data:

Conditions at engine ejection charge:
   Using a delay time of : 0.000 Seconds
      Velocity: 656.430 ft/s
      Altitude: 7790.843 Ft.

Recovery system data
   P:  main chute  Deployed at : 182.230 Seconds
   Velocity at deployment: 66.580 ft/s
   Altitude at deployment: 999.978 Ft.
   Range at deployment: -457.381 Ft.

   P:  drogue chute  Deployed at : 27.291 Seconds
   Velocity at deployment: 125.211 ft/s
   Altitude at deployment: 11898.389 Ft.
   Range at deployment: -3917.487 Ft.

Time data
Time to burnout: 12.300 Sec.
Time to apogee: 27.291 Sec.
Optimal ejection delay: 14.991 Sec.

Landing data
Successful landing
Time to landing: 244.251 Sec.
Range at landing: 815.626
Velocity at landing: Vert: -19.609 ft/s,
                     Horz: 9.349 ft/s,
                     Magnitude: 21.723 ft/s