HAB Launch SOP
!WORK IN PROGRESS! NOT FORMATTED YET!
Balloon Filling:
New England Weather Balloon Society's Procedure:
How to Inflate and Tie off Balloon
We use a similar method to this:
https://www.highaltitudescience.com/pages/how-to-inflate-a-weather-balloon
https://www.highaltitudescience.com/pages/tying-off-a-weather-balloon
NEWBS changes:
BEFORE attaching the balloon to the fill adapter and filling, we have SIX overhand loop knots pulled around the neck of the balloon (or more likely around the fill tube). 4 of these are strings that attach to each of the 4 spiral stakes in order to hold the balloon stable between fill and launch. 1 is attached to our payload train (down to the parachute, and from there to the radiosonde), and the last 1 is attached to a COUNTERWEIGHT (see below). Before we remove the balloon from the fill adapter, we slide ALL 6 loops up around the neck of the balloon.
We use a COUNTERWEIGHT to measure our neck lift instead of a pull/fishing scale. After running our balloon calculator, we take the "Neck Lift" spit out by the calculator, subtract the weight of the fill adapter attached to the balloon, and fill a bag or bucket with water bottles until it reaches that remaining weight. This is tied to the balloon using a short segment of string (only a few feet) using one of the 6 loops mentioned above. As the balloon is getting close, we watch until it is able to consistently lift the counterweight without dropping it back down again. At this point, we stop filling.
When removing the balloon from the fill adapter, be VERY careful not to let go of the balloon, and also make sure to only grab it by the thick part of the neck. Then we cut off the counterweight.
Here is a picture from a previous launch, showing the balloon staying completely stable in the wind after being tied down to 4 stakes. This takes the stress away as you give speeches, do final preparations, etc. Once you're ready to launch, grab the neck of the balloon and cut these strings. Then you can walk with it to the final lift off spot.
Note: Make sure you have room downwind before any trees or buildings, so it has plenty of space to clear any obstacles. The flight path prediction will show you which way it's expected to go. Ascent rates higher than 5 m/s will go straight up pretty fast.
Our procedure:
Roles
Helium tank handler
Responsible for the helium tank
Ensures the tank is secured properly
Responsible for ensuring the regulator is undamaged
Controls flow of gas going to balloon
Balloon handler
Responsible for the balloon and ensuring its handled properly
Ensures the correct amount of gas enters the balloon
Ensures the balloon is tied down properly before filling begins
Photographer
Takes close-out photos
Takes event photos
Tracking/Chase/Manager
Responsible for checking GPS lock on the ground
Responsible for calling in a NOTAM
Responsible for alerting an airport if the balloons in flight predicted landing is near or on there grounds
PR person
Explains what we are up to to strangers that may walk up
Outline:
Tank prep
Tank arrives at site
Details to be flushed out at a later date
Tank is checked to ensure it is in accordance with the RIT gas tank handling guidelinese
Regulator is attached, again following the training provided by RIT
Tube from regulator to balloon setup area is laid out
Site prep
The launch site needs sufficient open area down wind to clear the tree line
The launch site needs to have sufficient distance from inhabited areas that in the first 1000ft of accent the balloon does not pass over a dwelling
A tarp is layer out and staked down
Four steaks are planted and line of sufficient length for anchoring the balloon is attached
The payload area is established, this could be a table or on the ground depending on the site and type of payload
Balloon prep(done with nytril gloves)
Balloon Is laid out on the tarp
Anchor strings are slipped around the neck and loosely tightened
Filling adapter is attached to the balloon
Payload Prep
Payload is strung up according to the line order
Payload is layed out in strait line away from the launch pad
Close out is completed in accordance with the payloads prep procedure
Balloon filling & Handling
The tank operator and balloon operator must have good & immediate communication(withing earshot) or radio
Balloon handler puts the fill tube into the balloon and makes sure its not going to fall off
Balloon Handler watches for the scale to reach zero(to know the correct amount of helium is in the balloon.
Balloon Tie off
Balloon is tied off
Launching
Safety are removed
Launch procedure blah blah
Procedures
Transportation
Tank Prep
When the tank arrives at the site it is secured with ratchet straps to (IDK, what can we get in the field that could restrain a tank properly
A regulator is attached to the tank
Correct pressure rating
Correct gas type(ie. don't use a hydrogen regulator with helium)
Undamaged threads on both side
The helium tube is run to the launch tarp
Ensure not a tripping hazard, don't let the tube hang. Have it run along the ground
Turn the valve of the tank on
Turn it slowly
Turn it all the way on
Site Prep
Site requirements
The launch site needs sufficient open area down wind to clear the tree line
The launch site needs to have sufficient distance from inhabited areas that in the first 1000ft of accent the balloon does not pass over a dwelling
Lay out a tarp big enough for the balloon and some hand tools
So the balloon is not scratched or in the grass
Add steaks
4 steaks to hold down the tarp
4 more to be a safety catch for the balloon
(Optional) table setup, helpful for payloads generally
Table space is generally used for payload and holding tools
Balloon Prep DONE WITH GLOVES
Layout balloon
Balloon should unroll, don't spend to much time making it perfect, the less you touch the balloon the better
Backup ropes
Put the backup ropes over the neck of the balloon and very loosely tighten them with a slip knot
Attach inflator
Attach the inflation tube to the neck of the balloon
Check it will not slip out easily
Tighten backup ropes above the flare in the inflator to keep the balloon grounded
Payload Prep(All payloads will be different, these are more guidelines to follow)
Follow Payload Procedure
Check battery's are charged
Check payload is “armed”
Check payload has GPS lock and is transmitting/Decoding on receiving station
SONDE Trackers
Sondes cases have had NWS stickers removed
Sondes are powered on using fresh energizer ultimate lithium AA out of the pack
Sondes are checked to have lock and be decoding on ground station laptop
Line prep
Tie line items to the line/inline
Ensure the line items are attached in the correct order
Double check knots
Check all carabiners are taped shut