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Virgin Launch of an F Engine and Nike Smoke

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tfrielin

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Well, after much hand-wringing I finally got my Nike Smoke to the launch pad and successfully launched it with an Aerotech F26-6FJ engine. This was a milestone for me as it represented the first time I didn't use an Estes engine (1/4A through E sizes) since I began flying rockets back in the Johnson Administration.

It was an impressive display of black smoke and satisfying throaty roar at liftoff.

But, it was a windy day--too windy--and the Nike Smoke shuttlecocked into the wind, not gaining as much altitude as I expected. As a result, the rocket nosed over and was screaming back down as the parachute opened. That's where things went wrong.

The nose cone and parachute separated from the body and shock cord-----the former drifting over our heads leisurely and into a tree branch, the latter landing high up in the crown of a big oak tree where I thought it would stay permanently.

We could see the nose cone/parachute clearly even if we couldn't retrieve it and I could see the nose cone had been cracked. I initially thought it was caused by stress from the acceleration of the ascent. But now I think, given the late deployment of the 'chute, that maybe the nosecone slammed into one of the fins as the parachute opened, causing the gash in the nosecone.

Well, it turned out those stiff winds blew the rocket body out of the tree the next day and it was recovered. We had already left for home by then, so I haven't had a chance to examine the fins to see if maybe there might be evidence that my theory is correct about a fin/nose cone collision caused the nosecone's gash.

So, long story, short---partial success. Got two more F26 engines and another Nike Smoke kit to build as a replacement and will try again.

Meantime, does anyone have a suitable replacement or substitute nose cone for an Estes Nike Smoke??
 

Incongruent

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Can you attach pictures of the damage on the cone? It might be repairable.
 

Cabernut

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... But now I think, given the late deployment of the 'chute, that maybe the nosecone slammed into one of the fins as the parachute opened, causing the gash in the nosecone....
I have an onboard video of this very thing happening. Deploy about 2 seconds late, nose cone slams back into a hard point on the body, cracking it. Depending on the damage, you might be able to repair with a bit of CA or epoxy.

I haven't built one of these but I believe it uses the same 3" OD tubing that the Leviathan used and every other 3"(3.1") nose cone out there would be slightly too large.

Might be a good time to try making one from scratch. Conical nose cones are relatively easy to make compared to ogive.
 

ThirstyBarbarian

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Sorry to hear about the mishap. I think for the Nike Smoke on an F26, you might want a 4-second delay.
 

tfrielin

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"Can you attach pictures of the damage on the cone? It might be repairable. "

No, the nosecone/parachute is still up in the other tree. That's why I'm interested in finding a replacement cone.
 

Charles_McG

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My Nike Smoke also weathercocked strongly on a G33 in moderate winds. Deployed while horizontal at high speed. It ended up with a little wrinkle in the body tube, but not a zipper.

While the F26 might be listed, I think a little more thrust would be more happy-making. Like 50+.
 

ThirstyBarbarian

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I think it's true that othe Estes PSII nose cones for that diameter of tube will work. If it's an Estes 3" tube, then the nose cone for a Leviathan (or Big Daddy) will work. I saw a Nike Smoke with that kind of ogive nose cone once, painted yellow, and with a hornet decal --- looked nice!
 

tfrielin

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My Nike Smoke also weathercocked strongly on a G33 in moderate winds. Deployed while horizontal at high speed. It ended up with a little wrinkle in the body tube, but not a zipper.

While the F26 might be listed, I think a little more thrust would be more happy-making. Like 50+.
Yes, in thinking about the liftoff, I think the F26 engine was a little underpowered for the Nike Smoke. I blamed the too horizontal trajectory mainly on the wind, but I think the slightly slow acceleration as it cleared the launch rod indicated it needed more oomph, to use the technical term.

But now I'm invested in two more F26 engines and a complete other Nike Smoke kit so I'll hope for better flights.

Unless someone has a better alternative?
 

ThirstyBarbarian

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Yes, in thinking about the liftoff, I think the F26 engine was a little underpowered for the Nike Smoke. I blamed the too horizontal trajectory mainly on the wind, but I think the slightly slow acceleration as it cleared the launch rod indicated it needed more oomph, to use the technical term.

But now I'm invested in two more F26 engines and a complete other Nike Smoke kit so I'll hope for better flights.

Unless someone has a better alternative?
A G40 would be a good option. It seems to me like an F26 should have enough "oomph", but it might be a bit marginal, depending on the weight of your rocket, length of the launch guide, and strength of the wind. I used to fly my Leviathan pretty often on F20, F23, and F27 motors, and it usually worked out fine. I used a 6' rod, and tried to fly in calm conditions. I really think a 4-second delay is likely to be better for that rocket on an F motor.
 

Nytrunner

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Watch your glue and paint application. If you go overboard on big fin adhesions or primer layers, I can easily see a PSII kit creeping past the safe use of the lower thrust motors.

Since you have a new kit, take some time on it. Good chance to improve your glue and painting efficiency so you don't use more than you need.

When I overbuilt a leviathan for flying on ~25% H's last year, I won't fly it on anything marked less than 50N avg. (Even when looking at the initial thrust curves)
 

dpower

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I ran a quick sim on my Nike Smoke, which is on the heavy side (30 oz) due to dual deploy hardware in the NC. For an F26, there is only a 4:1 thrust-to-weight on an F26, 20mph off a 5' rail, 3.5s to burnout. Not enough thrust, unless it's dead calm, and a -4 delay would be required. I wouldn't fly mine on anything less than an F50/G40. With a 4' rod, it would be even more likely to have a poor flight. Hope your next launch goes better!

I don't think I've flown it on anything smaller than an H165!
 

Rex R

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mine has a dry weight of just under 18 oz. a flight sim says about 27.5 fps on an F22-5...maybe on a very low wind day. for me I like the F52-6,
Rex
 

MikeyDSlagle

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Yep. I would suggest one of these as well.
My first "not Estes" flight was my Wildman Sport, 27 oz dry, on a F42-4T. Around 41 ft/s off the rail. Low flight but straight up. Underwhelming smoke and noise though, comparable to an Estes D12 BP motor.
Can't help on the nose cone. But will also suggest longer shock cord/harness on your next one.

Mikey D
 

tomsteve

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thatsa bummer.
did you have the chute tied onto the nose cone or onto a loop in the shock cord?
 

DavidMcCann

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Yep. I would suggest one of these as well.
My first "not Estes" flight was my Wildman Sport, 27 oz dry, on a F42-4T. Around 41 ft/s off the rail. Low flight but straight up. Underwhelming smoke and noise though, comparable to an Estes D12 BP motor.
Can't help on the nose cone. But will also suggest longer shock cord/harness on your next one.

Mikey D
Yep. No flame, no smoke, decent whistle, but man... It's the motor that got me hooked on teleporting.

 
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tfrielin

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thatsa bummer.
did you have the chute tied onto the nose cone or onto a loop in the shock cord?

It was tied to the nose cone, I'm 99.9% sure---that's how I always do it. Not sure why it pulled loose.

But, thanks to all the replies here. I've learned two things: that F26 is too underpowered for the Nike Smoke. And I need to get a longer launch rod---my 1/4 inch diameter 3 foot length is too short and I'll get a five or six footer to replace it.

Only thing is, I've still got two F26 engines on hand----they are so expensive. Anyone got a suggestion for what is a suitable rocket for them?
 

Nytrunner

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The larger the rockets get, its recommended to tie the chute to the cord. That way the attachment point isn't experiencing double the force (1x going up from the chute, 1x going down from cord/rocket)
 

tfrielin

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The larger the rockets get, its recommended to tie the chute to the cord. That way the attachment point isn't experiencing double the force (1x going up from the chute, 1x going down from cord/rocket)

Ok thanks for that. I'l try it as I've got another NS kit to build
 

DavidMcCann

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TangoJuliet

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If you get a 6' rod (try Grainger) and a calm/no wind day, then you should still be fine with the F26 in a NS. The extra rod length combined with little to no wind will help immensely.
 

tfrielin

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If you get a 6' rod (try Grainger) and a calm/no wind day, then you should still be fine with the F26 in a NS. The extra rod length combined with little to no wind will help immensely.

Thanks--I've got a longer rod ordered from OnLineMetals, I think is the company.

Will try it on a calm day (no March winds!) and try to use up the other 2 F2 engines I've got. Then go for more powerful engines (if I still have the Nike Smoke in flyable condition, that is!)
 

tfrielin

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Bumping this thread back up: After two and a half years and three hurricanes, my Nike Smoke Nose cone and attached parachute finally fell out of the tree in which it was stuck in all this time.

Finally, my close-up examination confirmed that the nose cone did indeed slam into the yellow fin upon deployment. This explained the dent in the fin and its root cracking at the body tube joint. And now that I have the cone it is clear the collision sliced the top of the nose cone off.

Why the shock cord separated must be another issue---most probably my sub par construction skills.

But, after all this time, to summarize: The F26 motor was a little under powered for the Nike Smoke and six seconds was too long a delay.

Still, the good news here is: I recovered the body (as per the original post of mine here) got a new nosecone, shock cord and chute, and have successfully launched it as a Nike Smoke II (sort of) several times. And still have it after three successful Christmas Day flights.

So, lessons learned: I need to be a better builder, especially for shock cord attachment, F26 works ok, especially if it's not a windy day. And the Nike Smoke is one good flyer.
 

tfrielin

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And I said: "...F26 works ok, especially if it's not a windy day."

But next time I'm upping the engine to at least an F 32-4.
 
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