Mongoose.

[Dee55]

So now sitting here bored after the morning flights.. I'm gonna start the Estes Mongoose build. Anyone ever launched the Mongoose? If yes is it a good altitude rocket? I'll be using an A8-3 on frist launch and I'll just be doing single stage at frist.

 

[MALBAR 70]

The Mongoose is an easy build and a great flier. My son David has about a dozen flights on his. He likes the B6-0/A8-5 combo for our small, local field. At club launches it'll get up there on a C6-0/C6-7 stack. The only issue we've had, is that the top of the booster tube gets beat up a little bit after several flights.

 

[Wayco]

My very first rocket was an Estes Mongoose, and I still have that rocket ten years later. Great flyer, but I also got some damage to the top of the booster fincan until I modified it by splitting the tube in half and mounting the plastic fins in the middle. Now it actually tumbles and only occasionally breaks a fin. (old plastic) Most of my flights were on the C6-0/C6-5 combo.

 

[PDawg]

I had one and even though everything seemed perfect, it took off at an angle when the second stage kicked in. I now have several single stage versions (Estes Geeric E2X) that are great, but moved up to bigger single stage rockets for high altitude rockets. 2 C engines costs the same as an E. I'm just not into multi staging but I'm glad I tried it. To be fair I did get the main rocket back and rebuilt as a single stage, the booster disappeared and none of the 12 people watching ever saw it.

 

[BABAR]

depending on field size and visual acuity, go low on the motors, especially sustainers. a 1/2 A 18 mm or even downsizing with and adapter to a 13mm AT motor gives you all the joy of staging and a shorter recovery.

 

[Doug Holverson]

I'm building one as two stage Astro-Cam carrier.

 

[Back_at_it]

The Mongoose is a fun rocket to fly as long as you have the room. I've flown mine single stage a couple of times and I recommend that you go with the B6-4 first flight. It's little heavy for an A8-3 in single stage.

In two stage configuration I've flown it on B6-0/A8-5 combo for really low flights and gone up to C6-0/B6-6 for higher altitudes. I've never tried to fly it on a C6-0/C6-7 as I like getting my rockets back. I've also used a streamer on the higher flights for better visibility and closer recovery.

 

[jmasterj]

I like the B6-0 vs the C6-0 in the lower stage. The shorter burn gives you less chance of tilting vs the longer tail of the C6 thrust curve. The initial thrust is even slightly higher on the B6.

 

[afadeev]

So now sitting here bored after the morning flights.. I'm gonna start the Estes Mongoose build. Anyone ever launched the Mongoose?

Yes.
More then one. Rarely more than once.
And I still have multiple first stages to show for it!

If yes is it a good altitude rocket?

Yes, and and even better cruise missile.
The key to getting the second stage back is to use the highest thrust first stage motor you can find. Otherwise, the second stage goes horizontal, and goes missing.

I'll be using an A8-3 on frist launch and I'll just be doing single stage at frist.

See above.

HTH,
a

 

[4regt4]

Yes, and an even better cruise missile.
The key to getting the second stage back is to use the highest thrust first stage motor you can find. Otherwise, the second stage goes horizontal, and goes missing.

Had this happen also. B6-0/B6-6. Upon separation, it went sideways. Still scratching my head as to why. That was 6 months ago, it's still on display way up in a fir tree at the edge of the park....

Have an Estes Multi-Roc. It seems to fly straight on a pair of "B"s.

Hans.

 

[4regt4]

My very first rocket was an Estes Mongoose, and I still have that rocket ten years later. Great flyer, but I also got some damage to the top of the booster fincan until I modified it by splitting the tube in half and mounting the plastic fins in the middle. Now it actually tumbles and only occasionally breaks a fin. (old plastic) Most of my flights were on the C6-0/C6-5 combo.

I like this idea. The only 2 times I got to fly mine before it went sideways, the booster did a core sample. First time it was so deep in the ground, I almost didn't find it.

I bought a bundle of kits that included some that I had been looking for. Also included was a Mongoose, so it looks like there is another 'Goose flight in my future. I'll move the booster fins as you suggest. I might stack a pair of "C"s together for the next club launch and kiss it goodbye.

Hans.

PS: My previous Mongoose was before I started using OpenRocket. I wonder if OR will find some kind of instability. Sustainer fins too small? But I doubt it, as most tall rockets like this tend to be very stable.

 

[BABAR]

I like this idea. The only 2 times I got to fly mine before it went sideways, the booster did a core sample. First time it was so deep in the ground, I almost didn't find it.

I bought a bundle of kits that included some that I had been looking for. Also included was a Mongoose, so it looks like there is another 'Goose flight in my future. I'll move the booster fins as you suggest. I might stack a pair of "C"s together for the next club launch and kiss it goodbye.

Hans.

PS: My previous Mongoose was before I started using OpenRocket. I wonder if OR will find some kind of instability. Sustainer fins too small? But I doubt it, as most tall rockets like this tend to be very stable.

Has anyone simmed the booster by itself with an expended motor casing in OpenRocket or RockSim? I am curious whether the booster has Been demonstrated to be stable post staging. Seems like if so, would kind of not be an optimal design.

 

[4regt4]

There is a RockSim file on RocketReviews. I'll load it into OR and take a look. Both the whole rocket, and then I'll delete out all but the booster. Too lazy to build it up from scratch....

Hans.

 

[BigMacDaddy]

It is nice that the Mongoose is already painted / finished and it certainly flies fine as both a single-stage or boosted rocket. However, if you look at the kit it is so much cheaper than the Booster Bertha for example. I get that the Mongoose sells for $12-13 and the Boosted Bertha is $22-23 but the Boosted Bertha is a really impressive kit while I felt the Mongoose was pretty lacking.

 

[4regt4]

I'm kind of drifting toward the simpler, already painted kits because I hate to lose one that I've spent many, many hours building and painting. OTOH, stick a pair of "C"s in a Mongoose and just wave goodbye.

Hans.

 

[brockrwood]

So now sitting here bored after the morning flights.. I'm gonna start the Estes Mongoose build. Anyone ever launched the Mongoose? If yes is it a good altitude rocket? I'll be using an A8-3 on frist launch and I'll just be doing single stage at frist.

Love my Mongoose. I have the older version which is slightly harder to build (a little more gluing is required). Great flyer.

Make sure you have a second person to track the booster as it falls. It is pretty small. Avoid tall, booster-eating weeds.

 

[Dee55]

I'll prob just be flying it single stage. Idk if I would care for multi. But I am gonna leave the decals off. I rarely put any decals on my builds.

 

[4regt4]

There is a RockSim file on RocketReviews. I'll load it into OR and take a look. Both the whole rocket, and then I'll delete out all but the booster. Too lazy to build it up from scratch....

Hans.

The RockSim file has some errors, but I corrected most of them, at least in the booster part.

Seems the booster by itself is marginally stable, about 0.35 - 0.4 caliber (I'm still adjusting the mass of some of the little components). So it certainly could come in ballistic. Shifting the fin can forward a half inch or so hopefully will make it tumble.

Hans.

 

[Dee55]

The RockSim file has some errors, but I corrected most of them, at least in the booster part.

Seems the booster by itself is marginally stable, about 0.35 - 0.4 caliber (I'm still adjusting the mass of some of the little components). So it certainly could come in ballistic. Shifting the fin can forward a half inch or so hopefully will make it tumble.

Hans.

This rocksim iv been hereing about what is it? And where can I use it, mobile or PC?

 

[BigMacDaddy]

This rocksim iv been hereing about what is it? And where can I use it, mobile or PC?

You can use Rocksim or OpenRocket (or other packages) to simulate a model rockets aerodynamic characteristics. Both Rocksim and OpenRocket will open RKT files.

https://openrocket.info/https://rocksim.com/home

 

[Meatball 1]

Had this happen also. B6-0/B6-6. Upon separation, it went sideways. Still scratching my head as to why. That was 6 months ago, it's still on display way up in a fir tree at the edge of the park....

Have an Estes Multi-Roc. It seems to fly straight on a pair of "B"s.

Hans.

Just glancing through this thread. my Mongoose flew once just a few years ago on A8-0 to A. I recall that the top of the booster got toasted, though I do not remember the rest of the flight profile--whether it angled off oddly or not. I found this completely surprising because I had flown an Estes Scorpion 2-stage for several years and never had this problem (it was one of my old faithful favorites from the mid-late '80s through about 2003-ish when I lost the upper stage--and it's on my want-to-clone-someday list). Even so, I can see a couple of things that may affect things.

• The fact that the booster does not use a stage coupler means that it just drops off after the clear tape burn-through. This *might* present an opportunity for asymmetrical tape burn-through to rotate the un-couplered booster to the side and get some sort of thrust vectoring of the upper stage and even impingement of the exhaust on the tube (in my case). For normal coupled boosters, the tap burn-through happens, then the coupler ensures straight separation.
• Unlike the Scorpion, the Mongoose has a reinforcing ring at the top of the booster. It might be possible that this causes some sort of turbulent flow behavior (like Krushnic effect / Bernoulli lock) that prevents clean separation of booster. No idea if this is possible, and I think it's probably not a factor here. I may have just been very lucky with my Scorpion or unlucky with the one flight of the Mongoose.

The above may have nothing to do with anything (I'm just spitballing here), but I figured it might be worth a mention.

Josh T.

 

[4regt4]

This rocksim iv been hereing about what is it? And where can I use it, mobile or PC?

I was using OpenRocket, but it will load Rocksim files. OpenRocket is freeware, and quite good (I guess that's just an opinion...).

Edit: OoenRocket is Win, Apple, Linux compatible.

Hans.

 

[4regt4]

• The fact that the booster does not use a stage coupler means that it just drops off after the clear tape burn-through. This *might* present an opportunity for asymmetrical tape burn-through to rotate the un-couplered booster to the side and get some sort of thrust vectoring of the upper stage and even impingement of the exhaust on the tube (in my case). For normal coupled boosters, the tap burn-through happens, then the coupler ensures straight separation.

Josh T.

Forgot about their being no stage coupler. I suppose if the connecting tape burn through was not symmetrical, there could be "issues". I'll have to look closer at the design and see if a coupler could be incorporated.

Hans.

 

[neil_w]

OpenRocket is freeware, and quite good (I guess that's just an opinion...).

No, that is fact. (at least, the first part of your statement is)

 

[brockrwood]

Just glancing through this thread. my Mongoose flew once just a few years ago on A8-0 to A. I recall that the top of the booster got toasted, though I do not remember the rest of the flight profile--whether it angled off oddly or not. I found this completely surprising because I had flown an Estes Scorpion 2-stage for several years and never had this problem (it was one of my old faithful favorites from the mid-late '80s through about 2003-ish when I lost the upper stage--and it's on my want-to-clone-someday list). Even so, I can see a couple of things that may affect things.

• The fact that the booster does not use a stage coupler means that it just drops off after the clear tape burn-through. This *might* present an opportunity for asymmetrical tape burn-through to rotate the un-couplered booster to the side and get some sort of thrust vectoring of the upper stage and even impingement of the exhaust on the tube (in my case). For normal coupled boosters, the tap burn-through happens, then the coupler ensures straight separation.
• Unlike the Scorpion, the Mongoose has a reinforcing ring at the top of the booster. It might be possible that this causes some sort of turbulent flow behavior (like Krushnic effect / Bernoulli lock) that prevents clean separation of booster. No idea if this is possible, and I think it's probably not a factor here. I may have just been very lucky with my Scorpion or unlucky with the one flight of the Mongoose.

The above may have nothing to do with anything (I'm just spitballing here), but I figured it might be worth a mention.

Josh T.

Spitballing?

 

[4regt4]

Spitballing?

I used to be quite scientific about it. Diameter of straw, consistency of paper, amount of chewing. Could easily stick them on the cheek of my Sunday School teacher.

Hans.

 

[Dee55]

You can use Rocksim or OpenRocket (or other packages) to simulate a model rockets aerodynamic characteristics. Both Rocksim and OpenRocket will open RKT files.

https://openrocket.info/https://rocksim.com/home

Thanks

You can use Rocksim or OpenRocket (or other packages) to simulate a model rockets aerodynamic characteristics. Both Rocksim and OpenRocket will open RKT files.

https://openrocket.info/https://rocksim.com/home

 

[Dee55]

I was using OpenRocket, but it will load Rocksim files. OpenRocket is freeware, and quite good (I guess that's just an opinion...).

Edit: OoenRocket is Win, Apple, Linux compatible.

Hans.

Thanks.. I'll check it out

 

[4regt4]

Thanks.. I'll check it out

Looks a bit intimidating on first load, but if you find a file online of something you already have, you can see what is going on. At that point, the learning curve is surprisingly short.

Hans.

 

[neil_w]

Lad up the Simple Model Rocket example that’s built into the program. (File -> Open Example)