Princeton University attempt at a suborbital space shot?

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My opinion is to claim to reach space requires a dispassionate 3rd party to review the data and conclude altitude with an agreed to statistical certainty. At this point from what I have seen, this prize is still open.

All assumptions (Iike verticallity of trajectory) "proved" with data not a model.

Signed, Party pooper JD.
 
eggplant said:
Is there any evidence that Princeton actually got to space? A flight where both stages lit doesn't automatically mean a spaceshot, and they haven't announced anything yet. I guess I will wait until they post data, but based on other similar rockets flown by amateurs, I will be very surprised if their data supports that they got to space.
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I was being overly brief in saying they had a “successful” flight, at least for the first launch. For the second launch, the upper stage didn’t ignite.
By successful for the first rocket, I mean both stages ignited and at least visually both stages had nominal trajectories. I seem to remember 77 km being called out as an altitude for the first rocket. DId I hear that correctly?

Bob Clark
 
eggplant said:
Is there any evidence that Princeton actually got to space? A flight where both stages lit doesn't automatically mean a spaceshot, and they haven't announced anything yet. I guess I will wait until they post data, but based on other similar rockets flown by amateurs, I will be very surprised if their data supports that they got to space.
Click to expand...
Having a minimalist rocket helps with their goal. Their mass fraction would be significantly higher, because of not having recovery systems in particular. Carrying extraneous mass is a severe penalty with the rockets we fly.
 
OverTheTop said:
Having a minimalist rocket helps with their goal. Their mass fraction would be significantly higher, because of not having recovery systems in particular. Carrying extraneous mass is a severe penalty with the rockets we fly.
Click to expand...

I'm well aware of how they planned to accomplish the task, but I don't see how they could have done better than Curt von Delius on PHX4. That was a 98->98 two stage that reached 240kft. While it didn't have a composite case first stage and had recovery systems for both stages instead of just one, it also had a lot more impulse. I suppose drag makes a big difference, but I don't know if trading 50% of your sustainer impulse is worth it, especially when a big part of the point of two stage rockets is that the sustainer is lit at a high altitude to counteract drag.
 
A 98mm to 98mm rocket (PHX4) will not have optimum mass ratios, even though it is staged. The optimum ratio for staging is usually considered to be when the booster has a payload (sustainer plus final payload) that is the same mass ratio as the sustainer/payload combination. A 98mm to 98mm will have a mass ratio of somewhere around 50% which is a big performance hit.

If you get the ratios similar and the mass fraction somewhere around better than 10% then you are in the ballpark. It can be done by suboptimal ratios, but that requires more energy to counter the gravity loss in lifting the unburnt fuel.

A good example is that the mass fraction for the Shuttle was in the region of only 5%.
 
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We had a very optimal staging ratio and very low dry/structural mass in each stage. Chose highest Isp, highest mass fraction motors and high fineness ratio configurations, and very aerodynamically clean vehicle construction with LE radius <10 thousandths (.010") untouched on titanium LE surfaces after M6.1 hypersonic environment. Run the numbers independently.
 
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No official numbers until the official press release but over Mach 6 at 45 kft at s2 burnout.

Very vertical trajectory with s2 impact only 9 nm downrange (wind-weighted nominal s2 impact 12 nm downrange). John can post some pics of where he found the booster.
 
eggplant said:
I'm well aware of how they planned to accomplish the task, but I don't see how they could have done better than Curt von Delius on PHX4. That was a 98->98 two stage that reached 240kft. While it didn't have a composite case first stage and had recovery systems for both stages instead of just one, it also had a lot more impulse. I suppose drag makes a big difference, but I don't know if trading 50% of your sustainer impulse is worth it, especially when a big part of the point of two stage rockets is that the sustainer is lit at a high altitude to counteract drag.
Click to expand...

Drag makes a huge difference for smaller vehicles.
 
saadzmirza said:
We had a very optimal staging ratio and very low dry/structural mass in each stage. Chose highest Isp, highest mass fraction motors and high fineness ratio configurations, and very aerodynamically clean vehicle construction. Run the numbers independently.
Click to expand...
Sounds like you have done everything right, hence your success! :)
 
saadzmirza said:
We had a very optimal staging ratio and very low dry/structural mass in each stage. Chose highest Isp, highest mass fraction motors and high fineness ratio configurations, and very aerodynamically clean vehicle construction with LE radius <10 thousandths (.010") untouched on titanium LE surfaces after M6.1 hypersonic environment. Run the numbers independently.
Click to expand...

Would it be alright to post your sims?

Bob Clark
 
blackjack2564 said:
Saad.. what did you use to light the sustainers on last flights?
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BKNO3, mil spec, procured from the Army (as I understood it). Somewhere around $20/gram. (!)

I'm guessing around 10 grams in the sustainer. Probably at least 40 grams in the the booster.

Saad talked about this a while back in this thread:
https://www.rocketryforum.com/threa...rbital-space-shot.145647/page-13#post-1828685

Molding your own with Viton is at least 1/10th the price. But, it cannot be shipped after formulating/molding.
 
jsdemar said:
BKNO3, mil spec, procured from the Army (as I understood it). Somewhere around $20/gram. (!)

I'm guessing around 10 grams in the sustainer. Probably at least 40 grams in the the booster.

Saad talked about this a while back in this thread:
https://www.rocketryforum.com/threa...rbital-space-shot.145647/page-13#post-1828685

Molding your own with Viton is at least 1/10th the price. But, it cannot be shipped after formulating/molding.
Click to expand...

You mean MTV John or using Viton in a BKNO3 formula? That would be a new one on me. Kurt
 
ksaves2 said:
You mean MTV John or using Viton in a BKNO3 formula? That would be a new one on me. Kurt
Click to expand...

BKNO3 with Viton as the binder. Safer to dip or cast the pyrogen instead of pressing conventional bkno3. I've been making them for a couple years. There's a thread about it in the research forum. I've shipped out several pounds of boron and Viton. QuickBurst is now selling a dip/mold kit using the ingredients I supplied. It has slightly more energy than pressed pellets and is less static sensitive.
 
I see the kit but not the mold. Actually have most of the fixin’s On hand but using the kit would be nice.
Great job! Talk about safety? Wow! A heck of a lot better than using raw, augmented thermite powder.
That stuff would do the job but oh so dangerous. Look at it as a thermite powder with a very low heat of activation that burns at very high temp. An ematch (and less innocuous other things) could set it off.
I experimented with it years ago with ground testing and did it safely but the thought of an accident and resultant burns, prompted me to give it up. Now I might be able to successfully try staging. Now to find a mold
 
ksaves2 said:
I see the kit but not the mold. Actually have most of the fixin’s On hand but using the kit would be nice.
Great job! Talk about safety? Wow! A heck of a lot better than using raw, augmented thermite powder.
That stuff would do the job but oh so dangerous. Look at it as a thermite powder with a very low heat of activation that burns at very high temp. An ematch (and less innocuous other things) could set it off.
I experimented with it years ago with ground testing and did it safely but the thought of an accident and resultant burns, prompted me to give it up. Now I might be able to successfully try staging. Now to find a mold
Click to expand...
I believe the kit is intended as a dip type igniter product, however there is no difference between the dip type igniters and the molded type other than consistency of the compound .
 
rharshberger said:
I believe the kit is intended as a dip type igniter product, however there is no difference between the dip type igniters and the molded type other than consistency of the compound .
Click to expand...
There should be instructions on the quickburst site about making a mold. I've also described it in the bkno3-v topics in the research threads. Use hdpe 1/4" or 3 /8" plate. Drill holes through. Tape over the back side. Transfer pyrogen using on oral syringe.
 
jsdemar said:
There should be instructions on the quickburst site about making a mold. I've also described it in the bkno3-v topics in the research threads. Use hdpe 1/4" or 3 /8" plate. Drill holes through. Tape over the back side. Transfer pyrogen using on oral syringe.
Click to expand...

How about a segment of plastic soda straw? Could cut or peel it away or would it come out of a plastic micro-centrifuge tubes. Anywho, I’ll track down those instructions. Kurt
 
jsdemar said:
There should be instructions on the quickburst site about making a mold. I've also described it in the bkno3-v topics in the research threads. Use hdpe 1/4" or 3 /8" plate. Drill holes through. Tape over the back side. Transfer pyrogen using on oral syringe.
Click to expand...
Hi John,

Without posting formulas (and sorry, I don't have access to the research section) could you tell us the % binder in this / dried mix, or at least a ball park figure?
 
A recent two-stage I ran used a significant part of an E motor grain (blue thunder propellant) glued in place at the top of the M motor. I chose that over the other pyrogen methods because I didn't want to have to experiment with the other mixes. My ignition was at a lower altitude, but would it still work at higher altitude ignitions? I think it would, given the size of the grain compared to the igniter.
5GluedBTResize.jpg
 
ksaves2 said:
How about a segment of plastic soda straw? Could cut or peel it away or would it come out of a plastic micro-centrifuge tubes. Anywho, I’ll track down those instructions. Kurt
Click to expand...
The pyrogen sticks to the straw and most plastics. It also doesn't have enough surface area to evaporate the acetone. There will be voids, unlike epoxy binders that self cure without evaporation.
 
Hello All,

I've been sort of out of it for a bit having thyroid surgery, but today I found this thread and had a sudden realization. Did anybody notice what kind of launch system they were using for this flight? Yep, it was a brand spankin' new Wilson F/X single-pad wireless system. The Princeton team called me up on the phone asking if they could buy a wireless launch system for a special launch they had coming up that next weekend in New Mexico. This was Monday the 20th. We got things worked out and I shipped the system the next day to Space Port America in Truth or Consequences, New Mexico where it awaited their arrival. Two days later on Thursday May 23rd, I had my last surgery for thyroid cancer so I missed the launch itself.

So this morning, I was casually looking thru the RF threads when I saw the Princeton Univ launch thread. My brain went "Hey Look at that!" Then I saw the video of the launch and the gentleman who picked up the Wilson F/X wireless LCU-1w for the launch.

Whatever other problems they may have had with the flight, they had no troubles with their launch system! I'm pretty sure that this is the highest flight with Wilson F/X...……. so far.

Gotta admit that when we were talking rapidly on the phone, because these guys were desperate to find a system that they could get shipped to NM FAST, that the altitude they were aiming for didn't come up in our conversation.

But hey! Lots of fun all round!

"Reach for the Stars!"

Brad Wilson
Wilson F/X Digital Control Systems
 
RocketRev said:
Hello All,
Gotta admit that when we were talking rapidly on the phone, because these guys were desperate to find a system that they could get shipped to NM FAST, that the altitude they were aiming for didn't come up in our conversation.
Click to expand...

I thought the launch controller was supplied by Spaceport America. If had known they needed one, I could have brought mine. I've tested it to two miles. But, you would have missed a sales opportunity, and your follow-up testimonial in this thread. ;-)

Good luck with your health challenges!
 
RocketRev said:
Hello All,

I've been sort of out of it for a bit having thyroid surgery, but today I found this thread and had a sudden realization. Did anybody notice what kind of launch system they were using for this flight? Yep, it was a brand spankin' new Wilson F/X single-pad wireless system. The Princeton team called me up on the phone asking if they could buy a wireless launch system for a special launch they had coming up that next weekend in New Mexico. This was Monday the 20th. We got things worked out and I shipped the system the next day to Space Port America in Truth or Consequences, New Mexico where it awaited their arrival. Two days later on Thursday May 23rd, I had my last surgery for thyroid cancer so I missed the launch itself.

So this morning, I was casually looking thru the RF threads when I saw the Princeton Univ launch thread. My brain went "Hey Look at that!" Then I saw the video of the launch and the gentleman who picked up the Wilson F/X wireless LCU-1w for the launch.

Whatever other problems they may have had with the flight, they had no troubles with their launch system! I'm pretty sure that this is the highest flight with Wilson F/X...……. so far.

Gotta admit that when we were talking rapidly on the phone, because these guys were desperate to find a system that they could get shipped to NM FAST, that the altitude they were aiming for didn't come up in our conversation.

But hey! Lots of fun all round!

"Reach for the Stars!"

Brad Wilson
Wilson F/X Digital Control Systems
Click to expand...

At least one part of the project is well designed, constructed, tested and reliable.

M
 

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