76mm MD flight results query
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Post the file and I'll check it out.
fyrfytr310
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Post file! *salivates*
ECayemberg
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Motor?????
I have four flights on my 8.7 lb. Mongoose 75:
L995 to 15,216 ft.
L1115 to 18,773 ft.
L395 to 17,300 ft.
M840 to 28,905 ft.
The L395 was too slow out of the tower and laid over. Recovery was 3.5 miles downrange. All other flights were optimal.
L995 to 15,216 ft.
L1115 to 18,773 ft.
L395 to 17,300 ft.
M840 to 28,905 ft.
The L395 was too slow out of the tower and laid over. Recovery was 3.5 miles downrange. All other flights were optimal.
ECayemberg
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That's why I was asking about motors...good post!
29,973' on kba m1450w and just over 22k on an m3100wt. Need a bigger waiver closer to home so I can play more often!
Eric
I've sim'd a few out, but the goal is to fly with an M1650 Loki cocktail. I'm likely going to have to travel to do that, but I'd like a closer sim.... It's showing me about 18K and that's just not right.
This file is rough as hell, but should get in the ballpark I think-
View attachment mongoose 75FG.rktView attachment mongoose 75FG.rkt
This file is rough as hell, but should get in the ballpark I think-
View attachment mongoose 75FG.rktView attachment mongoose 75FG.rkt
Thanks.... either I'm blowing something in the sim or it's just not handling it right.... off by nearly 8 grand. (even when I readjust to 140 oz I still get 21500)
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AH HA! thats the issue...
I've never really thought about a flight like this, at all. Kinda bought it on an impulse and am trying to play catch up mentally.
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Do you have the parking brake on?
OK...the same smart arse reply..
Tony
OK...the same smart arse reply..
Tony
Igotnothing
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Nose cone is 3.14". Body tubes are 3.0"
You might have the CG more forward than a loaded rocket and wind in your sim is weather cocking the rocket.
You might have the CG more forward than a loaded rocket and wind in your sim is weather cocking the rocket.
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Dave,,
Ask Coleman to chime in on this...
As velocity increases past mach
Rocksim over estimates the increase in cd.....
The higher the velocity the further off Rocksim will be.....
Teddy
Ask Coleman to chime in on this...
As velocity increases past mach
Rocksim over estimates the increase in cd.....
The higher the velocity the further off Rocksim will be.....
Teddy
Nothing wrong with the files, 18K seems just about right. I don't have loki motors loaded, but I loaded a CTI- M-1670 and simulated to 17K. Looks like it is going to go that high.
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Plot Cd vs. Mach in Rocksim. The drag jump at Mach 1 is likely too extreme and lowering your flight dramatically. This make Rocksim nearly useless for any simulations that are transonic and supersonic. I stopped using it and now rely on RASAero or OpenRocket. Here is an example from my Blackhawk38 showing the huge difference in Cd
ECayemberg
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As others have stated, I don't trust Rocksim for high performance flights....well I don't really trust it at all, but that's a different story.
If you're looking for more altitude out of a Mongoose "easy", shorten the overall length and decrease the root (not span) of the fins.
-Eric-
If you're looking for more altitude out of a Mongoose "easy", shorten the overall length and decrease the root (not span) of the fins.
-Eric-
AlnessW
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That's exactly what I'm doing with mine - leaving out the payload bay and just flying the booster section/nosecone. Easy. OR sims it to around 36K on one of my 7600 loads - as always, seems a little generous...I'd be happy if I get over 30K...
watermelonman
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That Wildman Falcon references the M2245 numerous times; I have to wonder what it would hit.
Dwatkins
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35-40,000' at least!
Not really looking to optimize it, just know where it's gonna go
glenbo
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Hey Dave, I noticed the rocksim files for the Mongoose 75 That I came across were for the earlier Proline version which used a 54" booster & 25" payoad. The RW version has a 48" booster & 24" payload. I had to make the adjustments on the file which I am also trying to build using Open Rocket. I have the CF Mongoose 75. Is yours CF or fibreglass? When you start to address motor retention let me know. I have one of those placing the retention bulkhead for largest motor possible vs leaving enough room for recovery harness & drogue questions.
Mine is (or will be when it gets here) FG. I drew it up from scratch, using weights from RW's pages.
View attachment mongoose 75FG.rkt
I've talked to many people, and the retention plan is:
maybe some Al tape on the rear.
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