Selecting the filling balance weight - FB13

FB13 User Guide
Product status
Document code
M210768EN
Revision
F
ft:locale
en-US
Product
FB13
Document type
User guide

The proper filling balance weight depends on the weight of the payload (radiosonde and possible extra equipment) and the weight and shape of the balloon. To find out the correct filling balance weight, study the following figures and tables.

The figures illustrate the estimated bursting altitudes for TA and TX balloons of different weight, material, and carrying different payloads.

The TA balloon type is suitable for most soundings, while the TX balloon type aims to reach high altitudes when the temperatures are well below –75 °C in the sounding profile.

The values presented in the following figures are typical values taken from the manufacturer’s datasheet. The variation on the bursting altitude, as well as on the ascent rate, is quite high and depends on many factors, such as local conditions during the flight, the age of the balloon, and so on.
Table 1. Payload options for RS41, weight (g)
RS41 with external parachute RS41 with internal parachute (AUTOSONDE use) RS41 with small parachute 1 RS41 without parachute
RS41 Radiosonde 95 95 95 95
Unwinder 25 25 25 25
Parachute 70 40 20 -
Nozzle - 15 - -
Total payload 190 175 140 120
Figure 1. Bursting altitude (km), balloons > 200 g
Figure 2. Bursting altitude (km), balloons < 200 g
Figure 3. Bursting altitude (km), TA and TX balloons compared

Determining the nozzle lift

To achieve the rate of ascent of 320 m/min, you must determine the required nozzle lift according to the following tables.

For example, for a Vaisala radiosonde with external parachute (180 g) lifted by a 600 g balloon, the required nozzle lift is 1015 g, and for FB13, the nozzle lift is rounded to 1000 g.

Nozzle lift is the recommended lift given by the balloon manufacturer, and it refers to the weight the balloon is capable of lifting when filled. The FB13 nozzle lift is the weight that needs to be loaded to FB13 during balloon filling (including FB13 Filling Balance and the weights).

Table 2. Balloon filling for payloads 175 g, 190 g and 120 g, Balloons > 200 g
Payload
Vaisala radiosonde (~ 175 g), RS41 with internal parachute, AUTOSONDE use
Balloon weight (g) 200 300 350 500 600 700 800 1000 1200
Nozzle lift (g) 625 680 705 940 990 1045 1075 1145 1205
FB13 nozzle lift (g) 600 700 700 900 1000 1100 1100 1200 1200
Vaisala radiosonde (~ 190 g, RS41 with external parachute)
Balloon weight (g) 200 300 350 500 600 700 800 1000 1200
Nozzle lift (g) 650 705 730 960 1015 1065 1090 1160 1225
FB13 nozzle lift (g) 700 700 700 1000 1000 1100 1100 1200 1200
Vaisala radiosonde (~ 120 g, RS41 without parachute)
Balloon weight (g) 200 300 350 500 600 700 800 1000 1200
Nozzle lift (g) 535 595 625 850 905 960 990 1060 1130
FB13 nozzle lift (g) 600 600 700 900 900 1000 1000 1100 1100
Table 3. Balloon filling for payloads 140 g and 120 g, balloons < 200 g
Payload
Vaisala radiosonde (~ 140 g), RS41 with small parachute
Balloon weight (g) 30 50 100 200
Nozzle lift (g) 212 305 460 570
FB13 nozzle lift (g) 300 300 500 600
Vaisala radiosonde (~ 120 g, RS41 without parachute)
Balloon weight (g) 30 50 100 200
Nozzle lift (g) 190 280 435 535
FB13 nozzle lift (g) 300 300 500 600
1 Only with 30 g, 50 g and 100 g balloons