Dress rehearsal: more experience than we bargained for

Well, we had more of a rehearsal than we planned for, as everyone that helped this morning found out. So, the good news is that we got everything together, inflated the balloon correctly and had all systems go. We launched at 9:28. Our tether immediately broke and we were off to a real launch. It looked really cool and we could watch the balloon go up for at least 15 minutes. The good news is that we had planned on this maybe happening. The bad news is that something else failed and the GPS tracker stopped sending signals near the Blaine airport. Unless the GPS starts up again, our payload is lost.

So we learned several things today:

We need a real rope for the tethered balloon. The balloon has a lot of lift, so we could have 3 to 5 pounds of rope. That is a lot of rope.

We need to characterize the GPS some more. How does it perform in the cold? how does it perform on it’s side? how does it perform on it’s side in a Styrofoam cooler?

Below is a picture of some of the kids. We captured everyone in a movie that I can post on youtube – I will send you the link we I have it.

So, the real bad news is that we lost three gopro cameras, a GPS, a parachute, a still camera, and a balloon.

I propose that we rebuild and go with the original plan for Friday.

We have the approval from Sheila to rebuild and get ready for Friday launch.  I have sent out a list of actions.

Stay tuned.

Forrest

Dress Rehearsal moved to Sunday at 8:30

The weather looks nasty for tomorrow.  So, on to Sunday, 8:30 at Bel Air

Dress Rehearsal Launch!!!

Crew,

From the schedule below, we are going for the full launch, on a tether, on April 28th at Bel Air at 8:30. That is one week from this coming Saturday. We had talked about 8:00, but let’s let the kids sleep in. I expect this to take a full hour and 1/2.

Expectations: The intent is to have this be the real thing down to every detail. We will be testing everything, so we don’t fumble and disappoint the kids on the real day. So, please have everything ready to go.

If you cannot make this date and time, please let everyone know ASAP and If someone else can be responsible for bringing your child, that would be a bonus. This is our last chance before the big show, so please make this a priority.

Here is the full schedule:

May 4th: Launch day at Bel Air

April 28th: Dry run of everything assembled together. We will do a complete launch, on a tether, to test everything out.

April 22nd: All teams close to being done with their stuff, including testing.

April 14th: Meeting at 4:00.– DONE

April 9th: Everything ordered that can’t be purchased at Menards: like electronics, cameras, helium, parachute.– DONE

Notes from the April 14th meeting

April 14, 2012, Weather Balloon Meeting Notes

·         A YouTube video link has been sent to teachers to show in class.

·         We have three tanks of helium: one for the dress rehearsal and two for launch day. Each balloon needs one tank.

·         We need to start blowing up the two balloons 1 hour, 15 minutes before launch. It will take approximately 20 minutes per balloon. We’ll need a couple of regulators to inflate both balloons simultaneously. While inflating, the payloads should be readied.

·         The Peace Assembly starts at 9 a.m. At 9:30 the students will go outside and form a giant peace symbol. The balloons will launch at 9:45 a.m.

·         Rain dates: Peace Walk day or Track and Field Day.

·         The on-board cameras have 2.5 hours video capacity. They can shoot a 127° to 170° view. The untethered balloon payload cameras will be mounted with one pointing down, the other out one side.

·         The tethered balloon will also have a camera, pointing down.

·         Payload can be 2 to 5 pounds.

·         The traveling balloon will have 2 GPS for tracking. The recovery team will have a trailer full of equipment to aid in recovery. While a tricked-out ATV is coveted, the budget can’t sustain such an expense  :-)

·         Two teams will be needed: HQ and Recovery. The HQ team will monitor the tethered balloon and GPS tracking. The recovery team will have 2 vehicles. We will lose contact with the traveling balloon on the way up at 60,000 feet and will not reconnect until it has fallen back down to 20,000 feet. Models indicate that the balloon could land in an area from Taylor Falls to Eau Claire to Rochester. However, we are the whim of the winds.

·         Each classroom will make a prediction about where the balloon will land. A pin with each teacher’s name will be placed on a map.

·         Each kid on the balloon team may launch a small, colorful helium balloon during the launch.

·         PR? Sheila noted that it is being handled.

·         Saturday, April 28, will be a full dress rehearsal (inflate, tether, payload/equipment test). We’ll start at 8 a.m.

·         During the actual flight, real-time tracking can be done via Google Maps or a Facebook page that Sheila is working on.

·         Updates for the students could happen throughout the day on the Bel Air News. Perhaps the HQ team can handle this?

·         Matthew had a brainstorm: Perhaps we could use a food-saver vacuum system to seal and protect the cameras from condensation and/or a water landing. Applause followed and the meeting ended.

More thoughts from Kerry! (BHALDI)

More pointers:

A few off the top of my head thoughts:

• If windy, balloon filling can be really a challenge. You will want to have the balloons secured with tethers while filling.
• Balloon filling can take quite a while - easily 20-30 mins, more if you use the 'default' nozzle. We have borrowed a custom nozzle from Prof Flaten which worked really slick.
• Using carabiners to quickly clip stuff together can really help. I find that tying knots under stress is not a strength of mine.
• Make a checklist and follow it. A lot of things have to come together in a short amount of time. I sent you a copy of the one we used from our last launch.
• Have your recovery vehicle loaded and ready to go. Time goes quickly once the balloon flies, and the sooner you get to the landing site the better. You'll need a mobile hotspot for tracking the SPOT. Alternatively you can have someone tracking at home and providing you information via cell phone.
• The SPOTs need to always be facing up. We have devised a mechanism that achieves this - you may be able to see that from the pictures.
• Also having a forward recovery team that is in the area near the projected landing is extremely helpful, preferably outfitted with a mobile hotspot. We haven't done this yet but want to make this a standard part of our approach.
• It is actually possible on a clear day to see the balloon burst at 90,000 ft! I know, seems impossible, but it is not. You need to know where it is and be close to directly under it. Probably only possible for a forward recovery team unless atmospheric conditions keep the burst location close to launch.
• Can't remember if you said what time you are launching, but the earlier in the day the better to maximize daylight for recovery.
• The spreadsheet I sent also has a tab with a list of equipment for recovery.
• DON'T FORGET TO TURN ON THE SPOTS! ;) We forgot once but were lucky that we also had a Ham radio GPS unit tethered to the payload.
• DON'T FORGET TO TURN ON THE CAMERAS! Less catastrophic than forgetting the SPOTs but still pretty bad.
• Using the SPOTs can be a bit nerve-racking because of the 'dark' period. And sometimes there is a delay in the data being posted to the website. Most times we've been convinced that we've lost the payload, but so far they've always come back online. Be calm and patient - based on our experience it is likely data will get there.

Stream of conscience advice, but hopefully useful!

BHALDI has landed (we have help from pros)

Here is the email correspondence from the folks at BHALDI (Kerry and Ryan)  That is Kerry's picture over to the right of this post, as he is now tracking the blog. If anyone has additional questions, please email them to me and I will pass them on.
Here is the email trail:  Kerry's responses are in Blue

A good balloon filling/ascent speed/burst height calculator and flight track prediction software. We are using a package out of Cambridge at the website: http://habhub.org/predict/#!/uuid=369def4e1e897096767cc17d956d05db7c4837e2

We have used a couple different predictors. The one we use and the one used by Prof. Flaten is here: http://nearspaceventures.com/w3Baltrak/readyget.pl

It is not as easy to use - pretty clunky actually. I ran a model with each assuming a launch today at 10 am from Burnsville. The models produced similar bearings but the Cambridge one showed a significantly longer flight path. Not sure what the difference is - I think they are using similar data sources. I've attached the results from each. I also sent the results to Prof Flaten to see what he thinks about the predictor you are using. I like it better from a usability perspective, but accuracy is obviously pretty important. Could be that their atmospheric model may be Euro-centric and not be a good for North America.  FYI - I just reran the models and this time the results were almost identical. I think I must have chosen the wrong time period in the NSV model the first time. Thanks for the Cambridge alternative - we'll use that one as well in future launches and see which works better!

How have you prevented fogging of the windows in the cooler? We considered “filling” the cooler with helium right before sealing it. However, given the air pressure differences aloft, we may not want a tight seal on the cooler, such that the pressure equalizes.

We haven't used windows - we just cut holes in the cooler and stick the lenses through. That has worked pretty well with the still cameras, but we used a waterproof case around a Go Pro video camera and had condensation issues. We're still discussing how we will try to resolve those. Pretty sure trying to make the cooler airtight would result in a broken cooler.

What winds speeds have you experienced aloft? We are thinking on how to minimize spinning and anything breaking/whipping in the wind. We have a pretty sturdy cooler picked out, but have considered a bait bucket for it’s better aerodynamics and it just seems like the Minnesota thing to do. The windows would be harder to put in though. Always trade-offs.

I'm concerned that a bait bucket would be a) heavy and b) non-insulating. Keeping the electronics warm enough to perform is one of the biggest challenges. We have used hand warmers in the past and are considering using some small battery-powered radiant heaters for future launches. Coolers, and foam in general, is a great combination of light weight and insulating.

We are planning on using the Spot GPS tracker. We are strongly considering renting two of them, and having redundancy on the GPS. Plus we would get more frequent position updates with two GPSs on board. Your thoughts? We found a rental place for $80/unit/month – all tracking services included.

SPOT is a good choice. We also have used Ham-radio based GPS units borrowed from Flaten. They are a bit more work and add some weight, but provide higher data resolution and also remain working at all altitudes, where the SPOTs shut off at 60,000 ft on the way up and turn back on at 20,000 ft on the way down. So you are in the dark for quite a while which is a bit nerve-racking. So far we are 5-for-5 though... (again, knock on wood).

Have you done anything to make the payload easier to find when it is back on the ground and/or anything special for if it gets caught up in a tree? We were thinking of attaching 100 feet of ribbon, so you could spot it easier and have something to yank it out of a tree by. We were considering a small weight on the end of the ribbon to keep it from whipping around in the wind and getting caught in the parachute.

We have not done anything, but we probably should do more. Not sure about ribbon, but we have considered putting a small Radio Shack siren on them. We have not used them yet because we have wanted the audio from the flight and didn't want an annoying siren throughout. Again, maybe we've been lucky and should be using the sirens, but so far so good...

update on Website and some email threads

Hi everyone,

I think I have found the best website yet. It is a group of parents, teachers and kids that are located in Plymouth, MN. They have launched five successful balloons. While the website doesn’t have a lot of instructions, you can get a lot from all of the pictures. More importantly, it seems like they are interested in helping out others. I have contacted them through voicemail and email. I hope to hear back from them.

This is the website:

http://www.bhaldi.org/

http://freemars.org/mnfan/The%20Works/2011-05-BALDI-3-4-Launch/

From here you can thread to their facebook page and google+. I think one point of contact, me, would be good at this point, so please don’t contact them yet.

All aspects of the launch are coming together nicely, across all of the teams. We have GPS tracking identified, parachute, balloons being inflated.. all Very Cool! We need to order long lead items asap, so forward your purchase information to me and I will collect them up and forward them to Sheila.

If anyone is interested in going to the NOAA weather balloon launch site to see one go up, please contact Steve Helland. We are thinking either a Saturday or Sunday at 6 pm – in Chanhassen – 45 minute drive.

Also, I will be posted as much info on the blog as possible:

http://belairballoon.blogspot.com/

I think it is likely that we will meet at Bel air next Saturday, the 14th. I think it is also likely that we will try to inflate a balloon and test launch it on a tether. Stay tuned for details, but for sure the meeting is at 4:00 on the 14th.

Four weeks until Launch!!

Some more email details:

From Scott Ehrenberg 

scottehrenberg@comcast.net

If I learned anything from our model rocketry project last summer - just cut some holes in the parachute! It should drop pretty fast.

GPS TRACKING TEAM REPORT:
When can/should we move on GPS tracking expenditures? The only GPS tracking device that looks viable is the Spot GPS Messenger. New this device costs $150 at Sports Authority plus additional $100 basic activation/service plus additional $50 "tracker" service which allows for web-based map tracking of the balloon's path.
Rather than spend $300 for new, there are several businesses that rent this device. Assuming we can recover it and return it in one piece (no small assumption given the recovery team personnel assigned to this project!) will significantly reduce costs.

http://www.lowergear.com/product.php/id/261

According to the above site all required service / subscriptions are included with the rental.

My favorite quote from the above link: "If you push the 911 button to be rescued, you are responsible for all related costs of that effort." So, make a mental note to not push the 911 button, agreed?

Anyway, I think we will need this product in our hands for about a week prior to launch to play around with it and make sure it works, etc. And the web site advises at least 7 days advance notice on any orders. Absolute deadline to order would be April 20th.

Payload team be advised that this device weighs 5.2 oz. (147.4 g). not sure if this includes the weight of 3 AAA batteries required to run it or not. AAA batteries weigh 11.5 g. So worst case - call it 6.4 OZ (180 g).

Forrest,

The guy’s name is Ky Michaelson and his website is http://www.the-rocketman.com/content12.html

He has some interesting stuff – and seemed pretty friendly, so if we have any questions he may be a good source for some quick answers. I’d rather not pester him with multiple phone calls – but if we have any sticky spots we’re unsure of – maybe we could compile them and I could see what knowledge he can share.

Let me know if you think the parachute cost is ok and if we should go ahead with this. Sounds like he has them in stock so I don’t think it’s urgent. Maybe we put any questions together and we talk to him when either Marc or I pick it up in person. My first question would be to ask his advice on the parachute size – it seems from what I’ve looked at that either 4 ft or 5 ft should be fine – but good to get his validation.

Thanks,

Scott Ocel

Territory Manager / Truth Hardware / Ph-Fax: 763-781-8316 / Cell: 763-355-2699

From: Forrest Pape [mailto:forrestpape@comcast.net]
Sent: Wednesday, April 04, 2012 9:16 PM
To: Scott Ocel; MarcBergman@tierneybrothers.com; David Carley; Matthew Pehl; scottehrenberg@comcast.net
Subject: update: payload Weights

By changing to a K600 balloon, we only lose a couple thousand meters in height (10%) and it cuts down on the helium. So, since we are not going for the space station, I say we can go with whatever weight under the FAA limit of six pounds and still stay within our helium budget.

Forrest

From: Forrest Pape

Sent: Wednesday, April 04, 2012 9:10 PM

To: Scott Ocel ; MarcBergman@tierneybrothers.com ; David Carley ; Matthew Pehl ; scottehrenberg@comcast.net

Subject: Re: payload Weights

After a quick huddle with the recovery team (Matt), we decided that an hour of ascent time is ok. This means that we can have any weight payload up to the FAA limit.

So, ignore my previous email and go with Scott’s budget below.

The other thing that stuck in my radar is this guy in Bloomington. Do we have an expert in our backyard that we can pump for information?!? Can we buy other stuff from him cheap? Scott, let us know.

Some payload and ascent calculations. The key is that all but one of these payload/time options takes more than one cylinder of helium – at $200 per cylinder.

Forrest

various payloads and time to burst. 1000g=2.2LBS k800 balloon
3000 g
Burst Altitude:	22836 m		Ascent Rate:	6.85 m/s
Time to Burst:	56 min		Neck Lift:	7061 g
Launch Volume:	7.66 m3		7658 L	270.4 ft3
2000 g
Burst Altitude:	24228 m		Ascent Rate:	6.96 m/s
Time to Burst:	58 min		Neck Lift:	5686 g
Launch Volume:	6.32 m3		6319 L	223.1 ft3
1500g
Burst Altitude:	25056 m		Ascent Rate:	7.03 m/s
Time to Burst:	59 min		Neck Lift:	4984 g
Launch Volume:	5.64 m3		5635 L	199.0 ft3
3000g
Burst Altitude:	19948 m		Ascent Rate:	8.37 m/s
Time to Burst:	40 min		Neck Lift:	10915 g
Launch Volume:	11.41 m3		11414 L	403.0 ft3
2000g
Burst Altitude:	20922 m		Ascent Rate:	8.49 m/s
Time to Burst:	41 min		Neck Lift:	9440 g
Launch Volume:	9.98 m3		9977 L	352.3 ft3
1500g
Burst Altitude:	21473 m		Ascent Rate:	8.56 m/s
Time to Burst:	42 min		Neck Lift:	8690 g
Launch Volume:	9.25 m3		9246 L	326.5 ft3

From: Scott Ocel

Sent: Wednesday, April 04, 2012 9:58 AM

To: forrestpape@comcast.net

Cc: Marc Bergman ; David Carley

Subject: RE: payload Weights

Correction – available weight for contents is 55 oz, not 34.374 (lbs is 3.4375).

Thanks,

Scott Ocel

Territory Manager / Truth Hardware / Ph-Fax: 763-781-8316 / Cell: 763-355-2699

From: Scott Ocel
Sent: Wednesday, April 04, 2012 9:56 AM
To: 'forrestpape@comcast.net'
Cc: 'Marc Bergman'; 'David Carley'
Subject: FW: payload Weights

Forrest,

Have some data now that may help us finalize some elements of the payload. You can see some details in emails below – but here’s the key points

Cooler weight = 1.25 lb (20 oz) – cost $0

Parachute weight = 5 oz (5 ft chute size), cost $50

At 5 lb total payload this leaves 3.4 lbs ( 34.375 oz ) for the contents.

The guy who runs a mail order supply is in Bloomington so we can pick up a parachute and save $7.50 in shipping cost. This is half the price of a 3 ft parachute sold on Amazon – both are designed for this type of payload.

Let me know if you think this set up works and we can get the parachute secured. We might save some weight on the cooler – but this one has 1.5” walls and would allow us to carve out cavities to help secure cameras in the side and bottom.

Thoughts?

Scott Ocel

Territory Manager / Truth Hardware / Ph-Fax: 763-781-8316 / Cell: 763-355-2699