Ascent Rate: Descent Rate:
Date: 24th September 2013 Launch Landing:
Launch site: Rose Villa B&B , Pennant, Ceredigion, Wales
Landing Site: a hillside near LLanidloes
Balloon PAWAN 1600g ‘Balloon Helium’ fill 5.2 cubic m (2* T class cylinder)
Payload Weight 2400g
Equipment: Go Pro Hero 3, SPOT Messenger, CATTRAQ, and pumpkin
Ascent Rate: Descent Rate:
Safety was made a priority for this project. The following steps were made to ensure a safe flight:-
Pumpkin : The smallest pumpkin possible was used. It was made as light weight as possible and had a total weight of 1500gm.
Experiments were done to test the response of the pumpkin to cold conditions. I had to use other fruit as analogies as it was hard to get hold of pumpkins. Fruit was exposed to kitchen freezer conditions, over a range of time periods, and then taken out of the freezer. Changes in relative density were noted. Minimal increases in density following freezing over 1, 2, and 3 hours. After 20 minutes of time out of the freezer, a decrease in fruit density was noted.
The pumpkin was secured onto the central rod to stop it rotating. The flight video showed that vibration was reduced to a minimum and any play did not cause the pumpkin to fail.
Parachute : A 5ft Rocket man parachute was used in the flight. This would give a descent rate at ground level of 5 m/s at ground level. The parachute was tested with a static and dynamic weight to simulate the pumpkin and proved suitable. On launch day the tether was double secured to the parachute and payload to ensure the payload stayed attached to the parachute.
Tether. 4mm nylon cord was used as the tether. This was tested with a dynamic and static weight simulating the pumpkin. This was a football filled with nails.
Payload : The payload was tested with a dynamic and static weight to make sure it would not break. the pumpkin was simulated with a football containing nails. It was hung for 24 hrs to make sure it would not fail. It was also shaken vigorously for 30 minutes while dangled out of an upstairs window to simulate the shaking at burst and during flight. The materials performed well.
The camera was covered in polystyrene to protect against impacts. A layer of insulation was added to the base of the lower washer to protect against impacts.
The trackers were tethered in a polystyrene slab 10 m below the main payload. This was for ease of hanging the trackers and to ensure that this was the first part of the payload to land. Landing site photographs showed that the trackers stayed in the same area as the main payload. I deduce that on landed, the trackers were more or less directly below the main payload and not blown to the side; as in the design.
Flight path : The flight was flown over rural and remote locations in west Wales. The flight track was very close to the forecast done on the CUSF predictor. The balloon did burst early, possibly due to the balloon being left to stand for 3 hours before launch. There was no sign from the tracking that the balloon was a ‘floater’ and I estimate an ascent rate of around 5 m/s was achieved.
Flight Forecast / SPOT track
SPOT advises that the Messenger will not work if the antenna is pointing down. The tracker is in the white polystyrene box, pointing down.