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gpoehlein

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Club launch yesterday (Sunday). Nice weather, light breeze, so I decided to launch the Ranger (kit-bashed from a Bertha). Loaded what I thought were B6-4s into it and put the Q2G2 igniters it. After launch, it goes up less than 100 feet and then seemingly drag seps (never done THAT before, shoulder is long enough and usually tight enough). Continues to boost a bit longer as it king of tumbles upward. By the time the motors eject, it is on its way down with deployed chute.

The post mortem showed that I had actually installed two B6-4s and an A8-0. Bottom line is that A8 popped the chute before the B6s burned out. No damage to the model, just the modeller's ego! I'm still not sure how the A8 got in the wrong compartment (I use several Stanley compartment boxes for motor storage, and I live by myself so no-one has access to them but me), but that will teach me to just grab a motor of three out of the compartment without double checking them! ;)
 

TangoJuliet

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Doh! :facepalm:

At least it wasn't an expensive lesson learned. :wink:
 

K'Tesh

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Aren't the booster motors a different color than sustainer motors?
 

TangoJuliet

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They are, but from the description of the flight, I'm guessing this is a 3 engine 'cluster' model, not a 'staged' rocket.
 

K'Tesh

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They are, but from the description of the flight, I'm guessing this is a 3 engine 'cluster' model, not a 'staged' rocket.
I realize that... but from the description of the flight, the color should have been a clue. Unless there is a colorblindness issue in play here.
 

Bat-mite

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They also say "A8-0" on them instead of "B6-4," but I have made worse mistakes, so who am I to judge? :confused2:
 

Micromeister

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Single stage motors are printed in green. A8-3 and B6-4 are the same color print. All -0 booster motors are printed in red. Sustainer (Upper stage) motors are printed in purple.

Don't feel too bad Greg; Most of us Cluster nuts have had similar or worse experiences over the years. At least your A8-0 didn't backwards ignite the B6-4's ejection charge. I've had that happen with some mis-matched combo's in the past. Reminds me to always FP wad protect the forward ends of clustered motors.
Glad to hear no damage to the Rocket. She'll fly again hopefully with a trio of matched motors next time. I really like flying my Range Clone on 3- B6-4's also.

Cluster Motor Wadding Capped_13,18 &24mm_08-31-05.jpg
 
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TangoJuliet

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That's a good tip John. I've never flown any cluster models, so I wouldn't have known to do this.
 

Cabernut

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Sometimes "go fever" can play tricks on you. I once put a sustainer in backwards because I was in a rush to get back to the pad and GO! They actually can be lit backwards.
 

Bat-mite

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Sometimes "go fever" can play tricks on you. I once put a sustainer in backwards because I was in a rush to get back to the pad and GO! They actually can be lit backwards.
Interesting. I wouldn't have thought that. Ejection charge has to get through the clay cap and delay grain before getting to the propellant. Hmm.
 

Cabernut

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Interesting. I wouldn't have thought that. Ejection charge has to get through the clay cap and delay grain before getting to the propellant. Hmm.
I didn't think so either until the post-mortem. Perhaps the clay cap is weak enough to be broken by the booster burn-through, igniting the eject charge, then delay burns, and then the propellant burns in a weak nozzle-less fashion

This also didn't go as expected...:facepalm:
[youtube]C_ISnUZm6lc[/youtube]

loadstar_ii_lawndart03.jpg
loadstar_ii_lawndart04.jpg
 

hcmbanjo

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We've all loaded a wrong engine (or wrong delay) at one time or another -

Here's something I suggested to Estes back in 2010.
http://modelrocketbuilding.blogspot.com/2010/11/new-engine-designation-idea.html
The engines usually stick out by 1/4". The engine name could be seen on the exposed casing.
I never heard anything back -

Engine Color Bands_WEB.jpg

The labels shown were printed and glued on by me to show how it could look.
This is something we would all see when the clips are connected at the launcher.
This wouldn't prevent all wrong engine choices, but the engine name could be seen by the RSO at a club launch check in.
It would also give the solo flyer a second pre-flight check without pulling the engine out of the model.
 
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Forever_Metal

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Single stage motors are printed in green. A8-3 and B6-4 are the same color print. All -0 booster motors are printed in red. Sustainer (Upper stage) motors are printed in purple.

Don't feel too bad Greg; Most of us Cluster nuts have had similar or worse experiences over the years. At least your A8-0 didn't backwards ignite the B6-4's ejection charge. I've had that happen with some mis-matched combo's in the past. Reminds me to always FP wad protect the forward ends of clustered motors.
Glad to hear no damage to the Rocket. She'll fly again hopefully with a trio of matched motors next time. I really like flying my Range Clone on 3- B6-4's also.
now if i could get them to light at the SAME time...

fm
 

K'Tesh

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We've all loaded a wrong engine (or wrong delay) at one time or another -

Here's something I suggested to Estes back in 2010.
http://modelrocketbuilding.blogspot.com/2010/11/new-engine-designation-idea.html
The engines usually stick out by 1/4". The engine name could be seen on the exposed casing.
I never heard anything back -

View attachment 305343

The labels shown were printed and glued on by me to show how it could look.
This is something we would all see when the clips are connected at the launcher.
This wouldn't prevent all wrong engine choices, but the engine name could be seen by the RSO at a club launch check in.
It would also give the solo flyer a second pre-flight check without pulling the engine out of the model.
I just guided someone from Estes to your post, and was told that while the idea is sound, the reason they can't has everything to do with how the motors are printed.

Empty motor casings are picked up by something like a washboard conveyor belt that feeds them into the printer. A certain degree of movement by the casings is required by the printer to prevent jams. Once on the conveyor belt, they then roll under the printhead, and are then caught on the other end to be taken for filling, packaging, and distribution. If I understood correctly, when filling the motors, they are taken from the hopper, it doesn't matter from which end the motor is filled. So, the end markings you proposed wouldn't work.

If the motors were filled before printing, the printing process could damage the propellent or the nozzles, or residues from the filling process could quickly damage the printer.

Estes tried to make the motor casings out of a dyed material, however the dyes degraded the cardboard's performance for motors.
 

ttabbal

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So print it on both ends of the motor case. Problem solved.

It's probably cost prohibitive in some other way, but hopefully they come up with something. I like the idea of the RSO being able to quickly verify the motor and delay.
 

BEC

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So print it on both ends of the motor case. Problem solved.
That's exactly what I said to myself before scrolling down.....just do it on both ends.

German-made Quest motors were marked on the ends kind of like that....but that's a paper label that's added rather than printing on the casing itself. And, it's not right down on the end so wouldn't show unless the motor stuck out at least half an inch....

GermanQuestMotor.jpg
 

gpoehlein

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Nope not color blind - just got in a bit of a hurry after trying to untangle a snarled parachute (the old Estes shroud line scheme). Finally gave up and replaced the chute completely. Then I just grabbed three motors from the compartment without really looking at them. Plus, the Ranger is friction fit and the tape covered the motor designation label, so wasn't visible until I pealed it off for the post-mortem. Like I said - that'll teach me to just "grab-n-go" my motors! ;)
 

hcmbanjo

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I just guided someone from Estes to your post, and was told that while the idea is sound, the reason they can't has everything to do with how the motors are printed.
Empty motor casings are picked up by something like a washboard conveyor belt that feeds them into the printer. A certain degree of movement by the casings is required by the printer to prevent jams. Once on the conveyor belt, they then roll under the printhead, and are then caught on the other end to be taken for filling, packaging, and distribution. If I understood correctly, when filling the motors, they are taken from the hopper, it doesn't matter from which end the motor is filled. So, the end markings you proposed wouldn't work.
If the motors were filled before printing, the printing process could damage the propellent or the nozzles, or residues from the filling process could quickly damage the printer.
Estes tried to make the motor casings out of a dyed material, however the dyes degraded the cardboard's performance for motors.
Thanks for the explanation on the engine printing.
I have Estes engines where the engine designation is printed on both sides but,
it is away from the ends by about 1/2". That would be covered by the motor mount tube in most cases.
Maybe there is some reason why the print image area is away from the ends of the engine.
 

pdooley

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i did something similar with a C6-0 in a Red Max, surprisingly short flight.
 

Woody's Workshop

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Here is one idea that should be used, maybe made mandatory.
You should mention this to NAR.

We've all loaded a wrong engine (or wrong delay) at one time or another -

Here's something I suggested to Estes back in 2010.
http://modelrocketbuilding.blogspot.com/2010/11/new-engine-designation-idea.html
The engines usually stick out by 1/4". The engine name could be seen on the exposed casing.
I never heard anything back -

View attachment 305343

The labels shown were printed and glued on by me to show how it could look.
This is something we would all see when the clips are connected at the launcher.
This wouldn't prevent all wrong engine choices, but the engine name could be seen by the RSO at a club launch check in.
It would also give the solo flyer a second pre-flight check without pulling the engine out of the model.
 
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