New Estes PSII E2X Mammoth model

Estes recently released another model in the PSII E2X product line.

Named 'Mammoth' the model is taller than earlier PSII E2X kits. It features the same nose cone as the Majestic model without the chrome plating and the fins from the Prowler model.

The body tubes are finished in a shiny gold/copper metal wrap.

Looks like a straight-forward build.

Good looking kit! Anybody see this at Hobby Lobby by chance?

Initiator001 said:

Estes recently released another model in the PSII E2X product line.

Named 'Mammoth' the model is taller than earlier PSII E2X kits. It features the same nose cone as the Majestic model without the chrome plating and the fins from the Prowler model.

The body tubes are finished in a shiny gold/copper metal wrap.

Looks like a straight-forward build.

View attachment 245808

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I picked one up at my LHS a week or so back. One of the guys that works there is a CMASS member and when I walked in, he pointed it out to me and said, "You know you want it." I caved under the immense pressure. The club discount made the price more palatable.

I haven't put it together yet, but it looks to be a pretty simple build. I may try to get it built for our last launch of the year on 11/22.

That's a tall rocket. Info on the Estes site says it's 59.1 inches. That's taller than a Partizon by a few inches, although it's 2" diameter instead of 2.5".

The packaging says it goes 1600 feet high, which is presumably on an F15. They need some kits that don't go quite so high. I watched someone fly a Ventris to less than 1,000 feet on an F15, and the flight was beautiful. I'd like to see more kits that would have that kind of flight on an F15.

pyrobob said:

Good looking kit! Anybody see this at Hobby Lobby by chance?

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I was at my local Hobby Lobby today and did not see it. The deliveries to this store come on Mondays, so maybe it will show up next week.

I wonder if that NC would make a good foundation for a PSII based Black Brant II or BBIII.

ThirstyBarbarian said:

That's a tall rocket. Info on the Estes site says it's 59.1 inches. That's taller than a Partizon by a few inches, although it's 2" diameter instead of 2.5".

The packaging says it goes 1600 feet high, which is presumably on an F15. They need some kits that don't go quite so high. I watched someone fly a Ventris to less than 1,000 feet on an F15, and the flight was beautiful. I'd like to see more kits that would have that kind of flight on an F15.

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That reminds me, I should try an F15 in one of my stealths at moffet…

The challenge with a Estes kit that flies under 1K on an F15 is the low thrust of that motor. That Ventris flight, while stable, definitely wobbled and weathervaned more than when flying on composites.

Estes really needs to make a 12" or even 18" saucer kit. Saucers fly great on long burn motors.

SCrocketfan said:

That reminds me, I should try an F15 in one of my stealths at moffet…

The challenge with a Estes kit that flies under 1K on an F15 is the low thrust of that motor. That Ventris flight, while stable, definitely wobbled and weathervaned more than when flying on composites.

Estes really needs to make a 12" or even 18" saucer kit. Saucers fly great on long burn motors.

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Yep. Low-thrust, long-burn motors are mostly for sending light rockets very high. If the rocket is heavy enough to stay low, then it takes off too slow and is prone to weathercocking. And with a long-burning motor, that can mean a hairy cruise missile flight, resulting in a crash!

My thought is that a very lightweight but very draggy rocket is what is needed. The light weight would allow the rocket to get up to a safe speed, but the high-drag would keep it from going very much faster overall. You mentioned saucers, which are great on long burning motors. I'd like to see a rocket with more saucer-like flight characteristics.

One place to start would be to make some lightweight rockets based on larger diameter tubing. Right now all the kits made specifically for the E16 and F15 are 2" airframes. The PSII builder kits use fatter tubes but also use heavier materials to withstand composite motors, and the rockets are too heavy for the BP motors. I think they need some fatter rockets built lighter for their BP motors. The rockets might be too flimsy for composites but would be designed for the low thrust motors.

I was wondering when someone would notice that kit. Like the size, if only it had an ogive cone it would be about perfect.

I don't get the altitude claims on this series. I'm coming up with 1100-1350' max. on an F15. Sure, with another motor no problem ...

Stopped by the HL in Grapevine twice in the past week but no joy. However, the HobbyTown USA in Hurst had the new Mammoth kit. It was my first visit there and they had a ton of really cool stuff crammed into a fairly small place. Meant to take a picture of the new Mammoth kit on the shelf but was side tracked by son getting into practically anything he could get his hands on. The store manager was really cool and I would recommend stopping by and taking a look around if you're in the neighborhood.

I wrapped up the construction of the new Estes PSII E2X Mammoth model today.

It's a tall one, over 59" tall.

I replaced the kit supplied 29mm motor tube with one that was 23" long. This improved the structural strength of the lower tube and allowed me to incorporate an AeroTech-like cooling mesh baffle system. It turns out that the Quest 29mm-2" centering rings that are used in several of the company's Advanced Rocketry kits fit just fine in the Estes 2" diameter body tubes.

I made an effort to use the epoxy sparingly in assembly of this model. The dry weight/mass of the model came in at 13.7 oz. The box lists 11.9 oz.

I will post pictures of the first flight. :wink:

I'm curious as to the exact shape/dimensions of the NC. Is it a cone, or does it have a shoulder behind the cone (which is my guess, based on the photographs)? I'm wondering if it'd make a good foundation for something like a Black Brant or Stiletto upscale.

I like the looks of that, thanks for sharing.

K'Tesh said:

I'm curious as to the exact shape/dimensions of the NC. Is it a cone, or does it have a shoulder behind the cone (which is my guess, based on the photographs)? I'm wondering if it'd make a good foundation for something like a Black Brant or Stiletto upscale.

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It looks like the same nose cone from the Majestic kit both fitting the 2" diameter body tube.
It does have the shoulder behind the tapered front:

https://www.estesrockets.com/media/instructions/009707_MAJESTIC.pdf

From those instructions:

I got one of these for a trip to Florida for my nephews from Hobbylinc. It looks great stock and a 5 year old can really participate in the build, and it is a fast enough build to keep their attention.



Below is something I made for my nephews, so excuse the stills but there are 2 onboard flight videos, they were on economax F23 FJ's and both were in the 800-900 foot range but I cant remember exactly and I cleared the altimeter.

[video=youtube;9hOcZSChiU0]https://www.youtube.com/watch?v=9hOcZSChiU0[/video]

Saturday December 6th was a mostly clear calm day at the Santa Fe Dam launch site.

My new Estes PSII E2X Mammoth model was ready to be launched.

After reviewing the mass of the model and the mass of any motor I could use to fly the rocket I settled on an AeroTech Econojet F20-7W motor. The California weight/mass limit is 500 grams/17 ounces for a model rocket. I had wanted to use an Estes F15-4 motor but the combined mass was too close to 500g/17oz limit and I didn't want the RSO to deny the flight with an F15 motor.

The air was calm at launch.

It was a great flight. The F20-7W motor really got that model moving, much more than a F15 motor.

Recovery was a bit of a walk as I had angled the launch rod out towards the large open area. The model suffered no indication of damage.

hcmbanjo said:

It looks like the same nose cone from the Majestic kit both fitting the 2" diameter body tube.
It does have the shoulder behind the tapered front:

https://www.estesrockets.com/media/instructions/009707_MAJESTIC.pdf

From those instructions:

View attachment 247336

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Dunno how I missed your reply hcmbanjo...

Anybody know how long the shoulder is? How long the NC is overall? I'd like to add it to the library I've created, and if it would meet a 2" BBII upscale's requirements.

Thanks!
Jim

Great pictures Bob!

Boosterdude said:

Great pictures Bob!

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Thanks John!

It helps to have good camera equipment.

Evilash said:

I got one of these for a trip to Florida for my nephews from Hobbylinc. It looks great stock and a 5 year old can really participate in the build, and it is a fast enough build to keep their attention.

View attachment 247834 View attachment 247836

Below is something I made for my nephews, so excuse the stills but there are 2 onboard flight videos, they were on economax F23 FJ's and both were in the 800-900 foot range but I cant remember exactly and I cleared the altimeter.

[video=youtube;9hOcZSChiU0]https://www.youtube.com/watch?v=9hOcZSChiU0[/video]

Click to expand...

Nice, straight flight!

Initiator001 said:

Thanks John!

It helps to have good camera equipment.

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Should have added, great build and review as well.

Stretched the Majestic Openrocket file and adjusted mass in accordance with various figures seen in forums to get an approximation Openrocket file. Simulation results with 48" launch rod:



View attachment Estes Pro Series II Mammoth approximation.ork

I am fairly new to model rocketry. I have been flying Low power Estes rockets for a few months and now have acquired two of the Estes Pro Series II rockets, an Ascender and a Mammoth. The Ascender has flown twice on F15 motors just fine. I have finished the Mammoth but have yet to fly it.

Has anyone flown the Mammoth on BP motors? Which BP motor would be best, I have a E16-6 and F15-6. I am a little concerned with the Mammoth weighting in at 2 oz more than the Ascender. Will a E16 get it off the rail fast enough? TIA for any advice.

The E will have a higher rate off the rod because it is lighter and a little more avg newtons.

I launched mine on an F23 which is over 4:1 thrust to weight but an E16 is a little over 3.5:1. I ran it a E16 on open rocket and with a 6ft rod it gets to 41.2 f/s. (575ft)

The F15 sims to 37.2 ft/s and the thrust to weight is approx 3.2:1. (975 ft)

I think you would be fine either way since Estes has both as acceptable engines for the Mammoth. I just wouldn't launch it in a lot of wind and get a long rod. Have fun

Thanks Evilash. I did indeed launch with both E16 and F15's today. We picked a light wind day as you suggested. Both worked fine, the E16 went to 545 ft and the F15 to 1056 ft. What would be the minimum acceptable thrust to weight?

Here is a short vid...

[video]https://www.flickr.com/photos/dhkaiser/16310125599/in/photostream/[/video]

dhkaiser said:

Thanks Evilash. I did indeed launch with both E16 and F15's today. We picked a light wind day as you suggested. Both worked fine, the E16 went to 545 ft and the F15 to 1056 ft. What would be the minimum acceptable thrust to weight?

Here is a short vid...

[video]https://www.flickr.com/photos/dhkaiser/16310125599/in/photostream/[/video]

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Cool, good flight

Heres a good thrust to weight thread

https://www.rocketryforum.com/showthread.php?14552-Thrust-to-weight-ratio-5-1-or-3-1

Thanks for the link, good reading! I am considering a two stage with the Ascender using the Estes Pro Series Booster along with a duel deployment. I am a little concerned about the T/W and speed off the rail. Open Rocket shows 24.2 ft/s off the rail. The minimum I have seen on the net is 32 ft/s.

dhkaiser said:

Thanks for the link, good reading! I am considering a two stage with the Ascender using the Estes Pro Series Booster along with a duel deployment. I am a little concerned about the T/W and speed off the rail. Open Rocket shows 24.2 ft/s off the rail. The minimum I have seen on the net is 32 ft/s.

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What's the length of the rod? You ideally want at least 35-40 ft/s, and if you switch to a longer rod it'll help a lot.

I agree on the rod.. I saw a ps2 base in your vid and that rod is not very long. Which one are you going to dual deploy? That tubing is pretty thin. If you want to do dual deploy I'd get a different kit but I probably over think things. You would launch on a g right? The takeoff weight on a 15 avg newtons with a avg bay would be a concern for me.