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jared185

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Hi guys
So I plan to launch my first mid power estes ascender in the next few days and am wondering how much land I might need for the first launch I plan to use the smallest estes motor I can find toll I see how it will behave and then move up from the I've got around 8 acres of pretty clear land at my brother in laws house with few only two houses on it would that be enough room to launch and recover the rocket
 

jared185

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Also I don't want to create another thread for this because I've made a few here lately. but I just bought an estes mega red der max. I was wondering if i wanted to use the reloadable motors and I'm am building it in stock configuration which motor casings might work.
 

Bat-mite

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At a minimum, the smallest dimension of your field should be half the expected altitude of the flight. But in reality, if you use a large parachute on a windy day, it will travel well beyond that distance. Choose your motor, parachute size, and launch weather appropriately.

Here's a calculator that may help. Once you have your descent time, you can calculate the wind drift. Convert mph of the wind to fps, then multiply by your descent time.

For example, if your descent time is 50 seconds, and your wind speed is 5 mph, your wind speed in fps is about 7.5. Multiply by 50, and your expected drift is 375 feet. Now, this assumes a straight-up flight, with no weathercocking and no arcing over, which is very unrealistic. But it's a starting point.
 

Bat-mite

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Also I don't want to create another thread for this because I've made a few here lately. but I just bought an estes mega red der max. I was wondering if i wanted to use the reloadable motors and I'm am building it in stock configuration which motor casings might work.
The only two AT 40-120 motors that can safely lift an MDRM are the G64 and the G76. The AT SU motors are better (G77, G80, etc.). But after that you are straying into HPR. Even F and G motors with more than 80 N average thrust require Level 1 to purchase.
 

SaturnV

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It all depends on the wind. Wait a little wind and no looking rocket in the nearby village :)
 

jared185

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So I'm not looking to get a level 1 in the MDRM I want it just as a mid power rocket as I purchased a different rocket for lvl 1. So my question is since I'm new into this area and usually had low power rockets which specific casing would you recommend and would you have a website link to said casing
 

Bat-mite

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So I'm not looking to get a level 1 in the MDRM I want it just as a mid power rocket as I purchased a different rocket for lvl 1. So my question is since I'm new into this area and usually had low power rockets which specific casing would you recommend and would you have a website link to said casing
Well, as I said, you could go with the Aerotech 29/40-120, but you will be limited to two motors, the G64 and the G76. Your other option is CTI (Cesaroni) Pro29-3G, but you'll only get one safe motor out of that, the G54.

Aerotech makes a few single use (SU) motors that would suit you, but they are more expensive. G74, G77, G78, and G80 will work.

I recommend using rail buttons instead of 1/4" lugs because you will be able to use a longer launch rail and improve your stability off the rail.

Estes originally released the PSII kits to use their own rebranded AT SU motors. The MDRM is really an HPR rocket that can launch on a handful of MPR motors, but the pickins are slim.
 

mccordmw

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The Ascender can launch on regular, old Estes black powder motors. Recommended Engines: E16-6, F15-6 (First Flight), F15-8. Personally, I love the F15-8. It has a lovely, slow ascent, and a dramatic 8 second pause before the chute pops. Here's my Trajector on that motor.

[video=youtube;aHIybHO6ZQk]https://www.youtube.com/watch?v=aHIybHO6ZQk&list=PLATTzdsvVjzeMmxXeitTfg1V KkxiuZnoj[/video]

Go to the NAR site for the safe, recommended launch site sizes for low-to-mid-power rockets. It's part of the NAR safety code found here: http://www.nar.org/safety-information/model-rocket-safety-code/

If you use an F motor, their table says the minimum site size is 1,000 ft.
 

Bat-mite

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And what may not be clear is that the 1000' is the shortest dimension of the field, not the longest or average. So a field that measures 850' X 12,000' would not meet the minimum requirement.
 

MALBAR 70

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I would leave the thrust ring out of the motor mount on the Mega Der Red Max. In the future you may want to stick a longer motor casing in it once the HPR bug bites. The AT 29/40 120 case will still work until then.
 

jared185

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Thanks for all the advice this forum and community has been great to me and my many questions so I have a question about the mega Der red max I just built the built the motor mount slid everything in the bottom of the rocket dry fit it and glued it in place went to do something while it dried and my son (6) comes walking through the house with my elastic shock cord which was put into place with the motor mount and cr's I go back to check and it has dried into place and he didn't move the motor mount or cr's but apparently took scissors to the cord and cut the cord all the way at the cr where it was tied now I'm wondering how to remount the cord which I just now bought some Kevlar cord to replace the cut one
 

scsager

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Hi guys
So I plan to launch my first mid power estes ascender in the next few days and am wondering how much land I might need for the first launch I plan to use the smallest estes motor I can find toll I see how it will behave and then move up from the I've got around 8 acres of pretty clear land at my brother in laws house with few only two houses on it would that be enough room to launch and recover the rocket
You need at least 500 x 500 feet (5.75 acres) to launch a "D" motor.

For "E" to "G" power the minimum launch site requirements are 1000 x 1000 feet (22.95 acres)

These dimensions are listed in the NAR safety code for low power rockets.

http://www.nar.org/safety-information/model-rocket-safety-code/
 

scsager

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Thanks for all the advice this forum and community has been great to me and my many questions so I have a question about the mega Der red max I just built the built the motor mount slid everything in the bottom of the rocket dry fit it and glued it in place went to do something while it dried and my son (6) comes walking through the house with my elastic shock cord which was put into place with the motor mount and cr's I go back to check and it has dried into place and he didn't move the motor mount or cr's but apparently took scissors to the cord and cut the cord all the way at the cr where it was tied now I'm wondering how to remount the cord which I just now bought some Kevlar cord to replace the cut one

The extra size and weight of this rocket/nosecone require a "strong" shock cord mount. That is the reason why the instructions have you attach the elastic to the plywood motor mount.

Now that your son "helped" you... You will devise an alternate "strong" mount. The main idea is it needs to be reasonably strong.

One easy solution is to make something like the standard "Estes tri-fold" shock cord mount. Same style used in most other Estes kits only much bigger to spread the load over a larger area. Once the glue has dried, you can reinforce this with a piece of fiberglass cloth epoxied over the top.

If you are using Kevlar, I would suggest making the shock cord at least 15 feet long. Because Kevlar does not have much stretch/give, it imparts a greater load to the mount. A longer shock cord helps by allowing the nose cone more room to slow down.
 
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