Pike NAR L3 Package (PDF)

Level 3 Certification Project – December 3, 2015
Tim Cubbedge – NAR 98225
Project name: AGM-33 Pike
Advisor: Gary Dahlke (L3CC)

Concept:
This Level 3 certification project consists of a Madcow Rocketry kit. The kit contains a 5.5 in. diameter G10 fiberglass
airframe, capable of accommodating up to 75mm M-impulse+ motors. It is a split 3-fin booster design, with a payload
section for main chute. The drogue recovery gear is contained in the booster section. Topped with a 20 in. filament
wound Von-Karman nose cone, giving the rocket an overall length of 92.5 in. Dry weight, including recovery gear and
electronics, rounds out at ~457 oz. (28.5 lbs.).
Certification motor:
Projected Max Alt:
Drogue deployment:
Main deployment:

CTI M1101 White
6994 ft. AGL (simulated)
Apogee
1000 ft. AGL

Fig. 1 – Dry weight

Fig.2 – Loaded weight (M1101)
Preliminary flight simulation data:
Center of pressure:
Center of gravity:
Mass at liftoff:
Total impulse:
Burn Time:

68.48 inches from nose (Open Rocket V15.03)
59.75 inches from nose (Open Rocket V15.03) [Loaded w/ motor]
39.43 lbs. (Open Rocket V15.03)
5197 N-Sec.
4.68 Sec.

Launch guide data:
• Launch guide length: 96.0 in.
• Velocity at launch guide departure: 60.0 fps
• The launch guide clears at: 0.301 Seconds
• User specified minimum velocity for stable flight: 50. fps
• Minimum velocity for stable flight reached at: 63.6 in.
Max data values:
• Maximum vertical acceleration (y): 7.17 G’s
• Maximum vertical velocity: (y): 768 fps
• Maximum range from launch site: 1063 ft. (based on 5 MPH wind)
• Maximum altitude: 6994 ft.
Landing data
• Successful landing
• Time to landing: 1548 sec.
• Range at landing: 1063 ft.
• Velocity at landing: Vertical: -18 fps
Component descriptions:
Nose cone:
Type:
Shape:
Length:
Shoulder:

Madcow Rocketry Fiberglass, filament wound
Von Karman
20.0 in.
6.0 in.

Payload airframe:
Type:
Outside diameter:
Inside diameter:
OAL Length:

Madcow Rocketry G10 fiberglass
5.5 in.
5.36 in.
22.0 in.

Main recovery:
Chute type:
Chute size:

Fruity Chute Iris Ultra with pilot and deployment bag
84 in.

Harness:

7/16” tubular Kevlar x 25 ft. long

Avionics Bay:
Type:
Outside diameter:
Inside diameter:
Length:
Bulkheads:

Madcow Rocketry G10 fiberglass
5.36 in.
5.214 in.
14.0 in.
0.25 in. x 5.360 in. DIA anodized aluminum

Flight computers:
Primary:
Missile Works RRC3
Backup:
Eggtimer Quark
Switches:
Flight computers: Removable key switch, 1 for each altimeter
Booster airframe:
Type:
Outside diameter:
Inside diameter:
OAL Length:

Madcow Rocketry G10 fiberglass
5.50 in.
5.36 in.
48.0 in.

Drogue recovery:
Chute type:
Chute size:
Harness:

CATO 30” with spill-hole
30.0 in.
7/16” tubular Kevlar x 35 ft. long

Motor mount:
Type:
Size:
OAL Length:
Centering rings:
Motor retention:

Madcow Rocketry G10 fiberglass
75mm
33 in.
4x 0.093” G10 fiberglass
Aero Pack quick change 75mm

Forward Fins (3 each):
Type:
Madcow Rocketry G10 fiberglass – precut & Leading edge beveled
Thickness:
0.188 in. G10 fiberglass
Dimensions:
See below
Aft Fins (3 each):
Type:
Thickness:
Dimensions:

Madcow Rocketry G10 fiberglass - precut
0.188 in. G10 fiberglass
See below

Tracking:
Main:
Secondary:

Eggfinder GPS
Com Spec. RF

Overall Dimensional drawing:

20”

22”

CP = 68.482”

63.875”

92”

48”

9.625”
17.875”

20.125”
6.875”

1.375”
2.75”

8.0”

5.5”

5.5”

Avionics wiring diagram:

Main 1

Drogue 1
M

Main 2

D

RRC3

Quark

SW 1

SW 2

M

Bat 1

Drogue 2

Bat 2

D

Construction Details:
The entire airframe is composed of 5.5 in. DIA. Madcow Rocketry G10 fiberglass tubing, with a wall thickness of 0.07
in.
The nose cone is a Madcow Rocketry, Von Karman shape, made from filament wound fiberglass
The fins are 3/16” G10 fiberglass Fins
Before any construction was performed, all fiberglass components were washed with soapy water. All surfaces to be
bonded were then scuffed up with 60 grit sand paper and washed once again with soapy water.
Motor Mount and fin attachment:
The motor mount is a 75mm x 33” long G10 fiberglass setup, with 1/8” G10 centering rings. Motor retention is
accomplished by use of AeroPack 75mm quick change retainer which was epoxied to aft end of MMT with JB Weld.
Once the CR’s were aligned & epoxied to MMT, the MMT was inserted into booster airframe. The fins were then
attached to the MMT/airframe assembly. Fins were tacked with JB weld & then with internal & external epoxy fillets.
Fore & Aft CR’s were epoxied to airframe. A Y-harness is to be attached to two 5/16” steel U-bolts on the top CR of
the MMT.
Proline 4500 epoxy was used for CR attachment to MMT.
US Composite epoxy was used for internal filets & general bonding
Rocketpoxy was used for external filets.

Figure 1. Y-harness

Figure 2. U-bolt nuts secured with epoxy

Figure 3. CR's tacked on MMT

Figure 4. CR epoxy filets to MMT

Figure 5. Top view

Figure 6. Longitudinal view

Figure 7. Fin slots with holes for internal filet injection

Figure 8. Fin sets prepped/sanded

Figure 9. MMT epoxied inside Booster