Model Rocket history question... gap staging.

[Dr.Zooch]

I know some folks who lurk here are actual model rocketry historians, and for them I have a question... when and how did the concept of gap-staging come about?

This is for a piece I'm authoring in an up-coming issue of Rockets Magazine. They're starting an area dedicated to low-power (18 and 24 mm) rocketry. Anyone who gives me any useful information will get credit of course.

 

[falingtrea]

I remember some information can be found in G. Harry's Model Rocketry Handbook.

 

[shockie]

dr. zooch:

I reviewed G.Harry Stine's 1st edition Handbook of Model Rocketry's chapter on multi-staging , which was first available in August 1965, and they isn't any mention other than the following about "Gap Staging".

In the section titled, "Ignition of Multistaged Models", he states the following," This stage-separation system works well if the distance between the two engines is not great and if the top-stage engine has a gently flaring exhaust nozzle".

G. Harry is clearly talking about gap staging here even if the term had not been coined yet.


I can do some further research and see if I can find a "first mention" in any of G. Harry Stine's writings about gap staging. It may take me a few days to review his various writings.

Perhaps somebody has a 67 edition they can review?

There's an Italian 67-69 edition online that I will also try to look up.


In addition :

Figure 7.6: Cross section of multi staged model rocket at various stages

clearly shows a diagram of a multistaged rocket with about an 1" length gap between the upper and lower stages.

The first multistaged rocket was flown by Orville Carlisle when he mated parts of two of his Mark II's together.

G. Harry Stine designed the "Universal Lower Stage" on 1958 which was sold thru MMI.

Del "Delano" Hitch NAR #3 pioneered both cluster and staged clusters in 1958. His TFB-3 cluster staged booster was obviously a gap staged rocket.

I will do additional research and report back here as I find anything new. No mention is needed for me as I'm just reporting what is publicly already in print..somewhere.

Terry Dean

because of copyright restrictions I can't reproduce these images here. I would asume Bill Stine has the rights to his father's books.

 

[shockie]

Ok I found this tidbit, but I tend to disagree.

The Mar/April 2007 issue of LAUNCH magazine has an interview with Irv Wait conducted by Mark Johnson. Mark is a well know, long time, old rocketeer from the early to mid 60's.

Quote:

" My favorite from the old days was the first kit you came up with using gap staging with black powder motors -- the Vega. "

"At least three people seem to have invented gap staging independently. Trip Barber did some tests in about 1974, Harry Stine a bit later. But my recollection was that you(speaking of Irv)had it out on the market and were working with long gaps between black powder motors as early as 1968"

The RDC gap staged Vega was the world's first kit using the gap staging technique that I'm also aware of.


My reference to Orv Carlisle mating his Mark I's and a diagram of his staging technique(not necessarily gap staging) dates to Jan-Mar 1957 in letters exchanged with G. H. Stine. These letters used to be online at Quest's website but seem to have been taken down.

There was also a posted photo which appears to show a Mark I on top of a another Mark I along with his later 2 stage Parabee's. At least that what the photo seems to show me. Did Orv cut down the booster stage ? Only Orv knows .

In my research of model rocketry history, one thing stands out clearly: different people developed the same idea,design or technique over and over again at various times. Because of the times (no internet) people independently in a number of cases reinvented the wheel, so to speak.


If I personally was to give credit as to who first did gap staging it would be Orv, G. Harry or Del Hitch or perhaps it was one of G. Harry Stine's "NAR Boys" from his old Mile-High section in the 1957-58 time frame. A lot of the original research and groundwork for future ideas in model rocketry were developedand tested at this time.

HTH

Terry Dean

 

[Dr.Zooch]

Thanks a ton Terry!

That's exactly the stuff I was looking for. Not that most or all of it would be written by me, but mostly to get it squared away in my own head so as to keep things in correct context.

Request your permission to publish "Thanks to Terry Dean" with the article.

 

[shockie]

Thanks a ton Terry!

That's exactly the stuff I was looking for. Not that most or all of it would be written by me, but mostly to get it squared away in my own head so as to keep things in correct context.

Request your permission to publish "Thanks to Terry Dean" with the article.

that would be fine. I will continue to see what I can dig up.

You might want to contact Trip Barber to see what his recollections are. He's been around a long time too, of course.

I have Trip Barbers report and he tested 3" gaps in 1978. His technical bibliography shows a 1971 MITCON report titled, "Separated Engine Staging", Joseph Sarkis which I will assume is gap staging?

Perhaps if somebody will look in their late 60's early 70's copies of HMR they can date GH Stine's involvement with gap staging.

Terry Dean

 

[shockie]

dr. zooch:

I have a correction for you. It now appears(?) that the 1st gap staged model kit was the 1962 Centuri Black Widow and not the 1968(or thereabouts) RDC Vega. The 62 Centuri catalog is at ye old rocketplans and its clearly gap staged, although it is not advertised as such. I assume Leroy Piester designed it.

hth

Terry Dean

 

[Dr.Zooch]

Your research historian bug is as bad as mine- once I get onto a good sluth subject, I can't quit until I have every last bit of information discovered... results in 13 books in publication... not to mention royalties checks.

Keep it up! I'm not under a hard deadline for the piece.

 

[Dr.Zooch]

From the plans at Jimz's I see that there is infact gap staging going on with the 62 Black Widow- there is a coupler with two vents on the interstage.

 

[Bazookadale]

From the plans at Jimz's I see that there is infact gap staging going on with the 62 Black Widow- there is a coupler with two vents on the interstage.

The plans on the JimZ site are the 1970 version. I bought the Black Widow from the '65 or 66 catalog and mine did not have the vents on the coupler. Centuri instructed you to "prime" the upper stage by putting jetex wick in the nozzle, sticking out an inch or so.I never made this work - the jetex would not ignite, the top stage fell to the ground and I would put it back on the pad and light the jetex to fly it single stage!

The vented coupler came several years later when Centuri came up with "Pass-Port" staging

 

[Dr.Zooch]

GREAT info!!!

Thanks!!

 

[Bazookadale]

dr. zooch:


In the section titled, "Ignition of Multistaged Models", he states the following," This stage-separation system works well if the distance between the two engines is not great and if the top-stage engine has a gently flaring exhaust nozzle".

G. Harry is clearly talking about gap staging here even if the term had not been coined yet.

That page also shows the technique of "priming" the upper stage with Jetex wick

Perhaps somebody has a 67 edition they can review?

I have that edition- it states

" At the present time, staged engines must be taped together to insure an air-start of the upper stage. At one time in model rocketry, before 1963 it was possible to have series-staged engines separated by as much as 10 inches and still get a reliable air-start. However, changes in engine nozzles to improve the performance of engines made the old method unreliable; increased combustion pressure in engines also was a factor, because this caused stages to separate before the combustion gasses had the opportunity to get up the nozzle of the upper stage engine "

The current edition of Stine's book describes Trip Barber's research on staging, which he presented in 1977. Bases on this paper Stine developed the idea of venting the lower stage and says it can be used to separate stages by as much as 12 inches with 100% success

 

[Dr.Zooch]

Outstanding!

See your PM

 

[Dr.Zooch]

The current edition of Stine's book describes Trip Barber's research on staging, which he presented in 1977. Bases on this paper Stine developed the idea of venting the lower stage and says it can be used to separate stages by as much as 12 inches with 100% success

I need to make sure I get this correct- as it reads a bit odd in the above statement. Stein developed gap-staging... correct?

 

[Bazookadale]

I need to make sure I get this correct- as it reads a bit odd in the above statement. Stein developed gap-staging... correct?

Hmmm I THINK you could say he invented the system of open vent holes just below the upper stage nozzle. Centuri had its "Pass Port" vented coupler around 1970 or so but that was not the same - the vent holes stayed covered until the stages started to separate.I have in front of me the first, second, forth and seventh edition of Stine's book. Somewhere in the mess I call a house I have the sixth edition and I THINK Harry mentioned that his system was different then Centuri's and he was the first to use open vent holes, but I can't find that book! May be , as others have suggested you should contact Bill Stine.

If you can get the current edition the info on gap staging starts on page 167 - I will retype a little bit

"If the shock wave of hot combustion gases was blowing the stages apart prematurely, I reasoned that we had to get rid of the pressure of the hot combustion gases in the lower stage body tube. So I vented the lower stage body tube by by punching two 1/4 -inch-diameter holes on opposite sides of the tube just below where the noxxle of the upper stage motor would be."


" Over a period of several months I flew over 100 two-stage flights with 100 percent success in upper stage ignition. Motors were separated by as much as 12 inches"

So I think that Harry was the first to publish this technique

 

[Dr.Zooch]

Thanks! Don't worry- I'll write it in a way that covers it all. I think the most important conclusion is that in the era before the internet, a lot of people were working on the same problems and finding similar solutions on their own.

 

[Rocketcrab]

The plans on the JimZ site are the 1970 version. I bought the Black Widow from the '65 or 66 catalog and mine did not have the vents on the coupler. Centuri instructed you to "prime" the upper stage by putting jetex wick in the nozzle, sticking out an inch or so.I never made this work - the jetex would not ignite, the top stage fell to the ground and I would put it back on the pad and light the jetex to fly it single stage!

AHA!!! I always suspected you were one of the "Light And Run" guys!! :y: [hint - so was I ]