- This topic has 12 replies, 9 voices, and was last updated 13 years, 1 month ago by
Kevin Osler.
Kevin Osler.-
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RichWallner
Last Sunday, the Proton team (Steve, Rich, James, Adrian, Dave, Ken & John, and Bear) met at Dave Smith’s house in Longmont to enjoy excellent BBQ pork & chicken made by Dave (thanks Dave!), and to discuss the future of the Proton.
We reviewed all of the Raven telemetry data, we looked closely at pictures & videos, including the HD video shot by Adrian’s friend (if you haven’t seen it, it’s the best video of the launch — make sure to watch in HD quality:
http://www.youtube.com/watch?v=8L8pit6wEN4&feature=plcp
and we discussed everything about the project — what went wrong, and what went right. As we talked, we all agreed that despite the overall failure & crash, that a lot of things went right — we all felt that we were very close to success. As such, everyone wanted to repair the rocket & try again.
So, I hereby announce the Proton project, version 2.0!
As we repair/re-build, we’ll be applying a bunch of lessons we learned on Proton 1.0. Most of the changes will be minor, but the most important changes will be to the stage 1 motor selection & sequencing. The cause of the failure was that only 2 of the 6 outboards ignited, and this caused asymmetrical thrust which pitched the rocket over — careful review of the video & Raven telemetry shows that the rocket was climbing straight up until the first outboard ignited. Outboards # 1, 3, and 5 failed to light because their timer/altimeter wasn’t turned on, and #6 appears to have failed because the central Ms burned through its igniter wire. As such, we’re going to make the following changes:
— the outboard motors will be reduced from K impulse to H or I impulse, to significantly reduce any asymmetrical thrust
— a 4th M will be added to stage 1 to replace the thrust lost by reducing the outboards (as planned and as shown in-flight, the rocket was stable with just the 3 Ms, but a 4th adds margin).
— all 10 stage 1 motors will be ignited at the same time. This reduces the risk & delays of “air-starting” and of burning through igniter wires. We plan to use long-burn H’s or I’s in the outboards to give time for the central M’s to come up to pressure and initiate liftoff. For effect (and for contrast with the central “Russell Red”s), smoky outboards would probably be best — Aerotech sells an H112 BlackJack (3.5 sec burn) and an I115 White Lightning (3.7 sec burn) which would work well & look cool. I’m not familiar with CTI’s offerings — are there similar CTI loads we could use?Among the other changes we plan to make is: all electronics will have manual switches. Although Adrian’s magnetic switches are great, when there are 5 other units already beeping, it’s hard to confirm the beeps from the 6th…
Because everyone on the team is a bit burned out (no pun intended) from Proton 1.0, we all agreed to table the project for a few months, and to target Mile High Mayhem 2013 for the Proton 2.0 launch. So, we’ll probably start the repair/re-build in the fall. Stages 1 & 3 suffered minor/moderate damage, and we believe they can be repaired. Stage 2, because it came down without a chute (the charge fired, but it didn’t open), was basically totaled and will have to be re-built. Conveniently, though, stage 2 was the simplest stage to build.
As you may have read, Steve Mashburn is moving to Grand Junction to pursue some great job & personal opportunities. We will miss his enthusiasm, knowledge, and leadership, but he is fully supportive of the repair & re-launch, and we will carry on without him. James & Ken will be our TRA L3 sponsors, and I will store all of the parts and spares at my house for the time being.
One other topic that was discussed was: dividing up the repair work and doing it at multiple locations, to make it easier for people to participate. Because the team already knows how to build the rocket, we could easily divide up the work by rocket stages — we could have a “south” team in Highlands Ranch/Lone Tree/Parker, a “central” team in Denver/Lakewood/Wheat Ridge, and a “north” team in Longmont/Ft. Collins, and then just bring the rocket together at the end for final integration.
As with Proton 1.0, participation and financial support will be needed from anyone who is willing & able. We’ll let everyone know when we’re getting ready to start work!
new2hpr
Personally, I’d highly recommend the CTI motors for any cluster, staging, air-start application. I’ve had great reliability results with them with no fancy igniter prep. The Smokey Sam would provide a great accent for James’ Red, but unfortunately no long burns. CTI has a “White” propellant that has about 2.5s burn in the H-J range, but I haven’t’ flown it.
On the wiring getting scorched, the trick I’ve used is to have the wiring conduits close enough to the motors so there’s not much slack length of igniter wire hanging down. Install the igniter, push the wire up the conduit, pull snug, then screw down the connections. Screw terminals on the aft bulkhead might work also, but that’s another connection to worry about.
For the multi-altimeter beeping issue, maybe wire up a headphone jack to each alt, in place of the beeper. Plug the headphones into each to confirm activity with no crosstalk.
Just throwing out ideas.
-KenKevin Osler
Sorry I missed the meeting a week ago. Long story but ended up doing some time in local hospital due to “Bad Telemetry and a poor flight plan by the doctors”. But, every mm of my airframe has been examined and cleared for flight, so I am good to go.
Did we find the missing Cess case? I think from the video I posted we should be able to print out a picture, grab a shovel and find it. A metal detector might help. I am hoping we are not in a fire ban on the 7th, but even if we are, I am willing to go look for it.
BEAR
The missing 3rd stage motor was found the same day and so we are complete. Ken, I liked what you were saying about headphones but why not try my stethoscope and listen in that way as we rebuild it, then we could decide if we need headphones and headphone jacks. Maybe if necessary, depending on the electronics, we attach different noise making devices and alarms to the electronic devices so that they emit different pitches or frequencies than their norm if more than one uses the same sounds. I think that if we listen in with the stethoscope and have the boards more spread out through the air frame, we will be able to hear everything properly. Especially on the 2nd stage. Have them on 3 sides/locations, and maybe more vertical separation between devices, we will be able to hear more clearly. Just a thought.
Ted Apke
I like the idea of having work going on at more than one location. I’d be grateful for the chance to participate.
I’ll be watching for any announcements.
Ted Apke
edward
I’ll just throw my ideas out there – I hope to be more involved in the re-build if I have the time.
I’ve talked to James but wondered if there was a way to do a pull pin ignition of the outboards that would pass TRA & NAR safety code. This way as soon as the rocket moves less than 3″ something would latch and light them. Less technology and less to worry about. Something like a relay or similar that latches an SCR. The less moving parts, the better.
As for the outboard motors, I agree that if you go commercial, CTI is the way to go for ease of ignition. Back in 2007 I worked with a group of high school seniors and they made 3 grain 38mm motors. We tested 7 motors before flight to validate their models and all used a 44/45 30 grain pyrodex pellet pressed into the top grain. Ignition was prompt when using an e-match threaded through the core of the pellet and into the grain. A plus is that the e-match lit the pellet, which stayed for a second and lit the motor. I’ve lit Pitch Black (ex version of a smokey sam) with it with no problems. Your cost for the motors is much less than commercial. If people wanted to, I could machine the 38mm cases very reasonably, material cost + 25%. You are looking at ~$30 for a 3 grain 38mm motor, closure and nozzle. And you get to use it after you fly the project. It could be a good introduction to research.
All in all, I was very impressed with the project and you guys did a great job!
Edward
Warren B. Musselman
Speaking of motor cases – I loaned a 75/6000 EX case to the group. Where is that case now? James? Steve? Someone else? I want it back or $100 for it. ASAP before it disappears into the back of someone’s shop.
By the way, I’d prefer the $100 – I have no use for the case and would love someone who does to fly it.
Dave Smith
Warren,
I have your 75 here in Longmont. I am home nearly everyday with this morning being the exception. You are welcomed to come by a grab it or, I will be heading by your place in the next week or two as I have visitors in who will be headed up to RMNP. No worries on it being lost or utilized, I have my hands full building a 4′ PAC 3 with a 54 mount.
Adrian
Ken, I liked what you were saying about headphones but why not try my stethoscope and listen in that way as we rebuild it, then we could decide if we need headphones and headphone jacks. Maybe if necessary, depending on the electronics, we attach different noise making devices and alarms to the electronic devices so that they emit different pitches or frequencies than their norm if more than one uses the same sounds. I think that if we listen in with the stethoscope and have the boards more spread out through the air frame, we will be able to hear everything properly. Especially on the 2nd stage. Have them on 3 sides/locations, and maybe more vertical separation between devices, we will be able to hear more clearly. Just a thought.
I like this idea. I think the stethescope would have worked if we had used it. I did make a last-second checklist for the avionics arming –but didn’t use it because my hands were tied up hanging on the tower. Simple things like having one person on the ground with a clipboard, checking off items on a pre-rehearsed procedure, would have prevented a couple of my errors in the countdown activity.
The electronics in the second stage were the Raven and the Tiltometer. They have different enough beeps that they were easily distinguishable during the 2nd stage arming. The trouble was with arming the booster electronics at the end when all the other Ravens were beeping, and me forgetting to turn the cameras on the 2nd time around.
BEAR
Adrian, I would be happy to work with you on developing procedures for location, arming, and testing; then committing it to a checklist that we could use together for the actual arming at launch. I am also thinking that we need holes in the lower bulkheads close to each motor so that we can stuff the ignition leads back into the fuselage and put a piece of aluminum foil tape over the hole. Then nothing is present to be scorched by the M’s.
RichWallner
new2hpr
Kevin Osler
BEAR
Ted Apke
edward
Warren B. Musselman
Dave Smith
Adrian- The forum ‘Archives 2012’ is closed to new topics and replies.