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Balloon Data

Totex balloon Data:

Balloon Weight (gr)20030035045050060070080010001200150020003000
Diameter at Release (cm)117123125130133142146150157179185195212
Volume at Release (cu.m)0.830.971.031.11.221.51.631.762.012.993.333.894.97
Gross Lift (gr)960111011851335140517201870202023103440383044705720
Nozzle Lift (gr)76081083588590511201170122013102240233024702720
Payload (gr)2502502502502502502502502501050105010501050
Recommended Free Lift (gr) 51056058563565587092097010601190128014201670
Rate of Ascent (m/min)320320320320320320320320320320320320320
Diameter at Burst (cm)30037841247249960265370078686394410541300
Volume at Burst (cu m)14.128.336.655.165.1114.2145.8179.6254.3336.5440.5613.11150.3
Bursting Altitude (km)21.224.725.927.728.430.831.832.633.933.234.235.437.9

Its worth noting that the data above is based on the use of Hydrogen rather than Helium.

Hwoyee Balloon Data:

Balloon Size (g)1003003505006008001000120016002000
Neck Diameter (cm)≤4.5≤6.4≤6.4≤6.4≤6.4≤6.4≤7.7≤8.3≤8.3≤8.3
Diameter at Burst (cm)18038041050058068075085010501100
Average Burst Altitude (m)16000190002100027000280003000032000330003600038000
Average Ascent Rate (m/min)200≥340≥340≥340≥340≥340≥340≥340≥340≥340

The Balloon Gross Lift is the lift generated by the volume of Gas. Hydrogen has a density of about 0.09 kg/cu m and air about 1.2 kg/cu m at normal atmospheric pressure - generating a lift of a bit over 1.1kg/cu m. Helium has a density of about 0.17Kg/cu m - generating a lift of a bit over 1.0Kg/cu m. Subtract the Balloon Weight plus the Payload weight form the Gross Lift to give the free lift. The Recommended Free Lift gives a Rate of Ascent of 320m/min (a bit over 1000ft per minute).

Heavier payloads can be carried than the values above - this will either reduce ascent rate, burst altitude (if the balloon is further inflated to compensate) or both. The following spreadsheet allows you to calculate the affect on burst altitude and ascent rates of various levels of fill and payload. To use: choose the balloon size and fill in the payload weight - then adjust the launch diameter until you get the desired ascent rate (normally about 320m/min) - the volume at launch will tell you how much gas you will need.

:guides:burst3.xls by Steve Randall

CUSF Online calculator

Online Ascent Calculator (imperial units)

Keep it simple beginners table

Balloon sizePayload weightHelium neededFree liftaprox. BurstParaChute size
300g150g0.84 cu m410g84,000ft18”
500g250g1.29 cu m570g93,000ft18”
800g400g1.84 cu m690g108,000ft24”
1000g500g2.23 cu m780g112,000 ft24”
1200g600g2.62 cu m890g115,000 ft24”
1500g750g3.21 cu m1040g117,000 ft30”

(the above assuming about 1000ft/min ascent rate)

“Free lift” is the amount of extra lift the balloon will have after lifting itself and the payload - its the thing that sets the ascent rate. Free lift is the extra weight that should be added (to the payload weight) when filling the balloon to nutral boyancy. Don't forget to take the extra weight off before launch.

Helium Cylinder Data

SizeVolume (cu m)Approx Price Price /cu m
Small 0.25 £20 BOC (Disposable Cannister) £80
Large 0.4 £30 BOC (Disposable Cannister) £75
L 10 1.81 £65 LBG £36
PT 10 1.81 £80 BOC Inc Delivery and Collection £44
V 1.81 £70 BOC You collect and return £38
N 10 2.62 £50 Lets Party Ipswich £19
L 20 3.62 £97 LBG Inc Delivery & Collection £27
T 3.62 £95 BOC You collect and return / £65 Party Days Cambridge £26 / £18
N 20 5.2 £85 Lets Party Ipswich £16
N 30 7.82 £125 Lets Party Ipswich £16
L 9.0 £150 BOC You Collect and return £17
L 47 9.05 £168 LBG Inc Delivery & Collection £19

These are 2008 prices - since then some Helium prices have risen - treat the above as a relative guide only.

14-03-2012—- more up to date helium prices - and cheaper than BOC too!

guides/balloon_data.txt · Last modified: 2013/05/27 16:07 by rocketboy