cjvannucci
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It looks cool, but aerodynamically and structurally speaking is a stretch. Good luck on timing the motors. I secretly hope I get to eat my words
It looks cool, but aerodynamically and structurally speaking is a stretch. Good luck on timing the motors. I secretly hope I get to eat my words
Anticipation...…..
As Nytrunner said, 6.2 oz is a significant fraction of a 1.2 lb rocket.It appears the Cargo Bay (which weighs 6.2 ounces) at the back of the rocket is a huge air brake. The Cargo Bay is removable and when it's not used during flights the apogee is 1,151 feet.
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Is the drastic change due to the aero drag of the larger diameter Cargo Bay transition?
As Nytrunner said, 6.2 oz is a significant fraction of a 1.2 lb rocket.
Ways to explore the data:
1) Remove the cargo bay and put 6.2 oz of additional weight in the nose. Check sim altitude................................. Apogee 843 ft ..... vs 798 ft = 45 ft higher
2) Put cargo bay back but override all its components to zero mass. Check sim altitude......................................... Apogee 938 ft ..... vs 798 ft = 140 ft higher
3) Restore cargo bay component masses and change its diameter to match main airframe. Check sim altitude.... Apogee 827 ft .... vs 798 ft = 29 ft higher
All this should give you an idea of the relative contributions of the different characteristics of the cargo bay on projected altitude.
[edit: probably easier to do those in the reverse order I listed them ]
1) Remove the cargo bay and put 6.2 oz of additional weight in the nose. Check sim altitude................................. Apogee 843 ft ..... vs 798 ft = 45 ft higher
2) Put cargo bay back but override all its components to zero mass. Check sim altitude......................................... Apogee 938 ft ..... vs 798 ft = 140 ft higher
3) Restore cargo bay component masses and change its diameter to match main airframe. Check sim altitude.... Apogee 827 ft .... vs 798 ft = 29 ft higher
Great to see the Aliens using a 4020 John Deere row crop with ROPs! Nothing runs like a Deere!
Aliens know tractors rule.
But remember also that the loss of thrust (and thus impulse) is merely according to the cosine of the cant angle. These look like - what? about 10°. That would mean only about 1.5% loss. At 20° you lose 6%. So it would take a tiny baby E to look like a D. (An Estes E12 would have to be canted about 43° to look like a D.)Trust in thrust. Canted motors lose efficiency the greater the degree of cant. So like Spock to Kirk in the Wrath of Kahn: E's can seem like D's. We are going to launch on 3 D's.
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