Princeton University attempt at a suborbital space shot?

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[edit]Was too negative in my first crack at this. This is a tremendous achievement for the USC team, and they deserve congratulations. Getting past the Karman Line puts them in a very small club.[/edit]

One thing that leapt out at me as I read the report was that the motor igniter was inserted with the rocket horizontal. It was then "safed" and the rocket was erected.

I'm not super-excited about that, especially given the VT issue earlier this year.

[edited again] Good reasons why they would have done it this way down below
 
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One thing that leapt out at me as I read the report was that the motor igniter was inserted with the rocket horizontal. It was then "safed" and the rocket was erected.

I'm not super-excited about that, especially given the VT issue earlier this year.
Given the size of the motor, I'm guessing there just plain wasn't a safe way to install it with the vehicle vertical. I wouldn't want to try and push an igniter all the way up that motor while it's vertical, and certainly wouldn't want to be on a ladder anywhere near it. I'm mildly concerned that it wasn't "safed" before being installed in the motor, but otherwise I'm not sure how I would do it better.
 
[edit]Was too negative in my first crack at this. This is a tremendous achievement for the USC team, and they deserve congratulations. Getting past the Karman Line puts them in a very small club.[/edit]

One thing that leapt out at me as I read the report was that the motor igniter was inserted with the rocket horizontal. It was then "safed" and the rocket was erected.

I'm not super-excited about that, especially given the VT issue earlier this year.

I greatly appreciate your concern!
The OLVT team built their rocket with the igniters for both stages permanently mounted in the motors, not capable of being removed without removing the forward bulkheads of the motors.
If the USC rocket could have had the igniter installed after being raised to vertical it should have, but NFPA doesn’t actually require that. It simply requires inserting the ignition device with the rocket pointing in a safe direction:
4.13.6 A high power rocket shall be pointed away from the spectator area and other groups of people during and after installation of the ignition device.
In the case of OLVT their rocket was pointed in an unsafe direction, directly towards another pad.
The USC flight was not a Tripoli Sanctioned Launch.
 
[edit]Was too negative in my first crack at this. This is a tremendous achievement for the USC team, and they deserve congratulations. Getting past the Karman Line puts them in a very small club.[/edit]

One thing that leapt out at me as I read the report was that the motor igniter was inserted with the rocket horizontal. It was then "safed" and the rocket was erected.

I'm not super-excited about that, especially given the VT issue earlier this year.
The main reason you can install igniters the way you do into small HPR motors is the height off the ground of the rocket on a typical launch pad, and the relatively small size of the head igniter. The pyrogen/ematch at the end is light enough that it can be supported by the wire, so all you have to do to get the igniter to the forward end is snake the wire up the nozzle using the few feet of space between the rocket and the ground to maneuver. By the time you get to L3 motors, the core is usually long enough and the igniter end heavy enough that the wire alone can't support it. You have to connect the igniter to a stick of some sort, and this stick has to be around the length of the motor. For most 1515 pads I have seen, the aft end of the rocket is far enough from the ground that this stick can be inserted straight into the core, maybe with a slight bend. For a motor with around 8 feet of propellant like theirs, they would need a 9'+ stick and it probably couldn't be bent too much, so the rocket would have to be 7' or so off the ground. Designing a pad that can handle a 300 lb rocket and support it that far off the ground is not practical. By the time the leads are shorted while they are installing the igniter, is it really much less safe than handling the motor itself?

For reference, when my team flew our O last year we used two 1/4" dowels taped end to end to install the igniter. The tower at FAR holds the aft end of the rocket a couple of feet off the blast deflector, so we were able to install the igniter with the rocket facing up as our motor had about 3' of propellant. This year, we doubled the length of the motor to a P so we won't be able to use a single piece stick. The current plan is to attach together dowels like tent poles as they are fed into the rocket. We considered the flag pole method that Derek Deville used on Qu8k, but decided against it because a misfire would likely lead to the motor having to be disassembled so the line can be replaced.

Congrats to USC! I have been rooting for them for a few years now and always love to read their blog posts. This is rocketry on a level that most of us can only dream of and they made it work. I'd love to see a reflight with a focus on better video (less spinning/coning, and a solution for the paint melting issue) but I bet they have their sights set higher.
 
Thanks to Jasper, Steve and Andrew for the quick responses. That all makes sense.
 
It was Tfish or someone of similar caliber that posted using plastic straws (cali contraband) on the igniter wire. They flex, they allow bending of igniter wire, but lined up in a column, they can keep an igniter head (boosted or otherwise) vertical (give or take a few degrees)
 
Thank you. I'm agonizing a bit over what to write. This is a serious subject I know, but we are chatting. Also, I don't want to give the impression that I'm dissing Princeton or USC or other institutions that have 'space programs.' Just trying to keep perspective on the big picture. To me, mentoring is mostly a professional relationship. I don't wish to fuss over definitions, and understand that a team may need the expertise of say a ME or EE for something, and it would be great if they could be connected to someone comfortable helping with that. I'm just thinking that if you ask for a volunteer TRA member (mentor) to help a university team that want to build a rocket for a sub-orbital flight, you probably aren't going to get many people to step forward. I mean, not many people have the bandwidth for something like that. Again, looking at the objective of helping students. We want to help students have beneficial experiences to help them in their future career after graduation, correct? So, will a company such as Blue Origin want to hire them because they need someone to help them launch into space? What do companies want? What do students need? I've had the opportunity to speak with many students when I'm at Friends of Amateur Rocketry (FAR) launches. I speak not only with the handful of students that seem to be in charge, but also the ones that just seem to be there. If you've been to these events, you know what I'm talking about. These students are intelligent and capable too btw. In my opinion, we should try and help them too and perhaps get them more involved. It's an investment. I wish I could tell any college student, TRA wants to help you in rocketry. We will help you obtain kits and supplies from participating vendors and we'll help with motors too. Your launch fees are covered and we have local members that will help you answer questions about your L1 and L2 projects. We want you to learn how to build and fly safely. So, instead of a few mentors that are willing to oversee specific large projects, you could have an army of TRA volunteers helping individual students and these students can share their knowledge with other students. Students are more likely to listen to one of their team members than someone from the outside directing them. What's the goal? Safety is important of course, but I don't think it's just safety.
 
Thank you. I'm agonizing a bit over what to write. This is a serious subject I know, but we are chatting. Also, I don't want to give the impression that I'm dissing Princeton or USC or other institutions that have 'space programs.' Just trying to keep perspective on the big picture. To me, mentoring is mostly a professional relationship. I don't wish to fuss over definitions, and understand that a team may need the expertise of say a ME or EE for something, and it would be great if they could be connected to someone comfortable helping with that. I'm just thinking that if you ask for a volunteer TRA member (mentor) to help a university team that want to build a rocket for a sub-orbital flight, you probably aren't going to get many people to step forward. I mean, not many people have the bandwidth for something like that. Again, looking at the objective of helping students. We want to help students have beneficial experiences to help them in their future career after graduation, correct? So, will a company such as Blue Origin want to hire them because they need someone to help them launch into space? What do companies want? What do students need? I've had the opportunity to speak with many students when I'm at Friends of Amateur Rocketry (FAR) launches. I speak not only with the handful of students that seem to be in charge, but also the ones that just seem to be there. If you've been to these events, you know what I'm talking about. These students are intelligent and capable too btw. In my opinion, we should try and help them too and perhaps get them more involved. It's an investment. I wish I could tell any college student, TRA wants to help you in rocketry. We will help you obtain kits and supplies from participating vendors and we'll help with motors too. Your launch fees are covered and we have local members that will help you answer questions about your L1 and L2 projects. We want you to learn how to build and fly safely. So, instead of a few mentors that are willing to oversee specific large projects, you could have an army of TRA volunteers helping individual students and these students can share their knowledge with other students. Students are more likely to listen to one of their team members than someone from the outside directing them. What's the goal? Safety is important of course, but I don't think it's just safety.

Richard,
After reading the above I don’t see any difference between our positions.
I want the students to have a great foundation for Rocketry safety. I don’t mean to imply that we have a bunch of mentors who are experts in space shots. We have more members than perhaps any other hobby organization who have done very high complex flights and that experience is valuable, but basic safety and basic Rocketry are what we can teach the most.
 
So TIL that the US Air Force Academy launched FalconLaunch VII out of White Sands in 2009 and some are claiming they were the original student team to reach space.

Twitter link with more info.
https://twitter.com/skulumani/status/1131351960622391297

And some quotes from the google drive link.
Air Force Academy cadets helped support Air Force space programs with the launch of a rocket from White Sands Missile Range early April 17.

Radar data shows the rocket’s boosted dart section reached an altitude of 354,724 feet. This set world records for both altitude and speed of universitybuilt rockets.

At the time of this writing the rocket and payload had not been recovered.

Does anyone have any further information regarding this flight or previous FalconLaunch attempts? Just curious as it's the first I've heard of it.
 
It was Tfish or someone of similar caliber that posted using plastic straws (cali contraband) on the igniter wire. They flex, they allow bending of igniter wire, but lined up in a column, they can keep an igniter head (boosted or otherwise) vertical (give or take a few degrees)

Some people may find some of my post silly or weird. I post them for specific reasons. I found/find it weird that engineering students could not/cant figure a simple solution to a simple problem..hence the reason I posted the below picture awhile back. This is not the first time somebody had problems inserting an igniter in a motor with limited space.

45899175641_f02b3a8809_c.jpg


Tony
 
RPL member here!

For the record, the gunk that got on the camera lens wasn't melted paint or anything like that. It was actually the entire outermost carbon layer being torn off the outside of the rocket. We use a "sacrificial" bidirectional carbon sheet wrapped on top of the wound layers to give us something to sand down, and as a buffer against erosion during flight. When we got the rocket back, that layer was completely gone, with the wound carbon completely exposed!
 
RPL member here!

For the record, the gunk that got on the camera lens wasn't melted paint or anything like that. It was actually the entire outermost carbon layer being torn off the outside of the rocket. We use a "sacrificial" bidirectional carbon sheet wrapped on top of the wound layers to give us something to sand down, and as a buffer against erosion during flight. When we got the rocket back, that layer was completely gone, with the wound carbon completely exposed!

Thanks for chiming in Jamie! Out of curiosity what's the plan to mitigate the fin damage your leading edges saw during the flight in future flights? I can't help but think that those frayed carbon fins were quite draggy!
 
Now to wait for the data. Would have been nice if they had a team member do narration. Wonder what happened to the 1st stage. Lost telemetry it seems at the higher speeds to prompt one to say something about it breaking up.
Later on, they got positions that seems to suggest the sustainer is intact. I wish them success. Kurt
 
The sustainer (upper stage) ignited which is good news, since that was the problem with their last attempt. Waiting for the confirmation they were able to reach space.

Bob Clark
 
No - It is today. Must have been a typo. They have the bird on the tower, and are mulling about the launch pad right now.
 
Actually, the booster is on the tower. The sustainer appears to be sitting on the prep table.
 
They need to use a written checklist. Whatd’ya use for upper stage/sustainer ignition? KnB? One of the sensitized thermites that can go off with an ematch? No formulas please on the open forum. A yes or no would be fine.
Did Rock 1 hit the mark? Fantastico, you had two projects to go for it. Awaiting for data for the likely candidate for success. Get the boosters back? Did the Rock 2 sustainer, did the deployment chain perform nominally even though it didn’t light or did it core sample? If you got Rock 2 back intact, can try again at a later time. Kurt
 
They need to use a written checklist. Whatd’ya use for upper stage/sustainer ignition? KnB? One of the sensitized thermites that can go off with an ematch? No formulas please on the open forum. A yes or no would be fine.
Did Rock 1 hit the mark? Fantastico, you had two projects to go for it. Awaiting for data for the likely candidate for success. Get the boosters back? Did the Rock 2 sustainer, did the deployment chain perform nominally even though it didn’t light or did it core sample? If you got Rock 2 back intact, can try again at a later time. Kurt
 
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