Return of the Estes Pro Series II Nike Smoke

[ShadowSpire48]

Yes, it's become apparent Estes DGAF about thrust to weight as they release and rerelease ever-heavier rockets for their low-thrust 29mm motors.

If the listed weight is empty weight - as your figures indicate and as others have said Estes' weights are given (though Estes themselves never replied to my inquiry about it) - then the peak TTW on the F15 would be about 4.3:1. That's an RSO call at a Tripoli launch. Even if the given weight is loaded weight, TTW peaks at only 5.2:1, not confidence-inspiring for a half-kilogram rocket.

The F15 has a slow build to max thrust though - nearly half a second - and depending how you interpret the thrust curve, "initial thrust to weight" as mentioned in the Tripoli rules could easily be said to be below 3:1 and not allowed to fly at a Tripoli launch at all, regardless if the listed weight is empty or loaded. I'll be interested to see launch speed in sims.

I don't think NAR has hard and fast TTW rules like Tripoli, but I sure hope I don't see these flying anywhere on Estes 29mm motors in anything but deathly calm air, and pointed decidely down range. (A D12 in an adapter is a lot more reasonable.)

Looks like a great kit to fly on composites though. At the prices Estes sell most of their bigger kits nowadays, they probably don't mind too much if they fly on the competitors' motors.

I have flown mine on an Aerotech E23 a few times and I wouldn't dare do anything lower, it's a little scary but does work well for small fields. Estes does have a notorious history of making kits and not testing them on their own motors. I would've hoped the current owners wouldn't have done the same stupid mistake.

 

[Art Upton]

Yesss. For example using a longer rail to compensate for lower thrust to weight.

Yes, you need at least 8 feet on this rocket when built light for the F15

But But; we all know it's going to be flown on AP motors anyway !!!

 

[Initiator001]

While I am glad to see the Pro Series II Nike Smoke model return to the Estes lineup I am puzzled as to why this particular kit chosen.

My thought:

The PSII Great Goblin kit uses a 3" diameter body tube with four fin slots. The PSII Nike Smoke also uses a 3" diameter body tube with four fin slots.

Could both kits be using the same body tube?
I do not have either a PSII Great Goblin or Nike Smoke kit that I can readily check out this thought.
Can someone measure both tubes/check the part numbers on the instructions and see if they are the same?
If so, this may explain why the Nike Smoke kit was re-issued as it would use an already exiting existing body tube.

 

[Art Upton]

While I am glad to see the Pro Series II Nike Smoke model return to the Estes lineup I am puzzled as to why this particular kit chosen.

My thought:

The PSII Great Goblin kit uses a 3" diameter body tube with four fin slots. The PSII Nike Smoke also uses a 3" diameter body tube with four fin slots.

Could both kits be using the same body tube?
I do not have either a PSII Great Goblin or Nike Smoke kit that I can readily check out this thought.
Can someone measure both tubes/check the part numbers on the instructions and see if they are the same?
If so, this may explain why the Nike Smoke kit was re-issued as it would use an already exiting existing body tube.

The Great Gob tube is about 3+ inches shorter and the slots are far down on the tube not up on it like the Nike.

They do sell the Nike Smoke 4 slotted tube as spare parts all this time. So it would have been blowing or injecting more noses that would have to be done to bring it back.

They Blew out the Smoke on the last run right when the Aerotech engines quit being sold to power it.

 

[Buzzard]

Estes does test their kits with the recommended motors, but they are in Colorado at over 6,000 ft above sea level. Here in DFW we are about 600 ft ASL, so a bit more atmosphere to deal with. IF the 17.5 ounce stated weight in the ad is correct, then with a 3.5 ounce motor it hits the 21.0 ounce recommended lift off weight for an F15-4.
As I mentioned above, my modified NS comes in at 22 ounces and loves Aerotech F67 single use and G64 reloads.

 

[Initiator001]

The Great Gob tube is about 3+ inches shorter and the slots are far down on the tube not up on it like the Nike.

They do sell the Nike Smoke 4 slotted tube as spare parts all this time. So it would have been blowing or injecting more noses that would have to be done to bring it back.

They Blew out the Smoke on the last run right when the Aerotech engines quit being sold to power it.

Thanks for checking on that.

Hmmm, another great theory goes in the trash can.

 

[Capt. Eric]

I can only assume they have read these boards, spoken to fliers, and have sales figures. They know what is popular and likely to sell well. So they can introduce new models with the inherent risk of a flop (see Blue Origin or Leaper), or reissue a model they know there is a solid market for (and price it high). Take the safe bets most of the time, and roll the dice only occasionally.

Again, just my assumptions, but I should think it makes some business sense.

 

[samb]

Estes does test their kits with the recommended motors, but they are in Colorado at over 6,000 ft above sea level. …

Repeated with emphasis added.

 

[ecargmij]

Spoiler Alert !

View attachment 652304

They listened?!?! Also an 18mm version. I can't wait

 

[bad_idea]

Your quote is only in relation to rockets with an active stability system. Otherwise, the word "initial" is not included in the code regarding T/W ratios.

Well the specific passage is "Initial thrust-to-weight ratios lower than 3:1 may only be authorized by an RSO if an active stability system is included," so it's quite clear that a purely fin-stabilized rocket with "initial" TTW lower than 3:1 is not permitted at a Tripoli launch, but the term "initial" isn't defined, making the passage somewhat ambiguous.

As I am sure you know, there are many variables other then the T/W ratio influencing an appropriate rail exit speed.

Certainly, and this is why I'm interested in seeing flight sims. Working in its favor are reasonably large fins which may lend it stability at lower speed. Working against it are a weight of 17.5 oz and a motor that takes 0.4 seconds to hit a low peak thrust*, and that it will most likely be flown off a fairly short rod, unless Estes breaks with tradition and supplies rail guides instead.

I ran some sims in Thurstcurve (which of course only shows rod/rail exit velocity EDIT: I meant only this as opposed to other factors of launch stability, not that it doesn't give other numbers) with stable velocity turned down enough for the F15 to appear in the results. My conclusion is that we had better hope that this rocket proves capable of achieving stability at exceptionally low speeds, or that people do the reasonable thing and fly them on composites.

* Don't get me wrong: I love the F15, just not in heavy rockets.

 

[rharshberger]

They listened?!?! Also an 18mm version. I can't wait

And its even more fun hot rodded with a 24mm MMT a JLCR, thin mill Top Flight chute and Aerotech 24/40 and 24/60 motors.

 

[Scott_650]

And its even more fun hot rodded with a 24mm MMT a JLCR, thin mill Top Flight chute and Aerotech 24/40 and 24/60 motors.

Kudos for getting the JLCR to work reliably in BT60 tubes! I’m about 50% successful

 

[Art Upton]

They listened?!?! Also an 18mm version. I can't wait

Want an 18mm motor version NOW? I have an Estes new one in a bag I could sell you*

* Says the 'Smoke Man

 

[Art Upton]

Or you could get them here : https://www.erockets.biz/estes-flying-model-rocket-kit-nike-smoke-est-7247-oop/

I think I saw them at 18.95 on Sirius Rocketry when Initiator posted, and now today I see a few places including them at $25.95

So they had to change their price now that they are going to sell them again , no discounts remember ?

 

[Art Upton]

And its even more fun hot rodded with a 24mm MMT a JLCR, thin mill Top Flight chute and Aerotech 24/40 and 24/60 motors.

I need to do that on the next Quest Plastic Fin can version I build next. I had been putting 18mm D motors in my my G. Harry Quest version, last flown at Geneseo that way. [That was a long walk to the very edge of the northwest of the field]

 

[Scott_650]

Or you could get them here : https://www.erockets.biz/estes-flying-model-rocket-kit-nike-smoke-est-7247-oop/

I think I saw them at 18.95 on Sirius Rocketry when Initiator posted, and now today I see a few places including them at $25.95

So they had to change their price now that they are going to sell them again , no discounts remember ?

At AC Supply the discount continues…

 

[Art Upton]

At AC Supply the discount continues…

Not the 40% it used to be, or even the 30%

 

[neil_w]

I can only assume they have read these boards,

I’m genuinely unsure about this.

 

[NOLA_BAR]

$69.99

 

[samb]

I say that price is about right. Looking at the specs and instructions this is a straight re-issue of the first run PSII from 2012. FWIW my well flown stock built model with some fin repair weighs a schosh over 18 ounces. Flown on composite F and G motors but never tried an F15.

 

[neil_w]

Why does the product page say "Challenging" build, and "complexity of the assembly process"? It's a 4FNC with molded plastic fins. What am I missing? The hardest part of this rocket always seemed to be painting the fins.

 

[WizardOfBoz]

The rocket is very nice looking, and the 3 inch tube size makes for an impressive rocket. But the idea that you'd fly this 1 kg rocket (per the rocksim file) on a motor with maximum thrust of 2.54 kgf (25 N) is a bit... optimistic. OR predicts that this combo reaches a 128 foot apogee and requires a 1 second ejection delay. That's kind of nuts.

The F40 and F67 seem to be more reasonable motors for this rocket.

 

[RokitFlyr]

I would say it's just the Estes rating system. It is a mid-power rocket, and involves multiple adhesives and stronger building techniques. Not the normal type of model rocket from them.

 

[markg]

F40 is usually the motor of choice for my PSII Smoke. I didn't set out to build it super light and it comes in at 16.6 ounces. On a 60" rail OR sims an F15-4 at 31ft/s which I would deem acceptable on a low wind day.

I flew another custom rocket that weighs 16.2 ounces at LDRS earlier this month on an F15-4. Nominal flight.

In any case, here's the PSII Smoke flying on an F40 which will definitely work

 

[samb]

JumpJet AKA The Chief Designer insisted in many posts here that F15 flights were doable. Who else has done it ? I'm game to try the next time I get my hands on some F15s.

 

[WizardOfBoz]

Its interesting that the OR/rocksim file gives a weight of over 900 g. 206 g for fin set. About 240 for nose cone. 139 for the body tube. 43 for the motor mount. 240 for the parachute. Plus the motor. I'm going to go over this - the total weight doesn't seem to reflect the individual weights in the file.

At 500g (overriding the rocksim file) I get reasonable flights, a TTW ratio more like 5, but a low (30ft/s) velocity off the rod. But a more reasonable 500 ft apogee. Of course a single real data point conquers the sim.

 

[neil_w]

JumpJet AKA The Chief Designer insisted in many posts here that F15 flights were doable. Who else has done it ? I'm game to try the next time I get my hands on some F15s.

It's certainly *possible*.... but it's also a good bit outside the safety guidelines that we are supposed to be following (hopefully). Estes has done this with LPR models as well. I realize they're limited by the motors they sell, but it's still frustrating.

 

[WizardOfBoz]

BTW, in doing a bit of research I noted that some BARs in NZ built a FULL SCALE REPLICA of the Nike Smoke. And it flew great - (on a purlple neon P10000 sparky!) near Mach 1 and 9000 feet AGL.

https://www.nzrocketry.org.nz/events/Havoc/nikesmoke

 

[MidOH]

I'll be building mine light.

Hang around with the wrong crowd, and you'll build nothing but bricks.Huge 1/4 radius fillets, big fillets on centering rings, papered or resin covered fins, too much spiral filler.........ick.

I haven't done a fillet on a centering ring in ages. Use a bit of scrap balsa instead. Way lighter.

 

[neil_w]

BTW, in doing a bit of research I noted that some BARs in NZ built a FULL SCALE REPLICA of the Nike Smoke. And it flew great - (on a purlple neon P10000 sparky!) near Mach 1 and 9000 feet AGL.

https://www.nzrocketry.org.nz/events/Havoc/nikesmoke

See also: https://www.rocketryforum.com/threa...-pro-series-ii-nike-smoke.187035/post-2599468