manoevre a balloon/bestuurbaarheid luchtballon

Hello newsgroup members,

Do someone know something about manoevreing (movement/direction control) of a balloon. Aircrafts do that by their flight controls, but what way does balloon pilots change direction of the balloon (if possible)?

Hallo, weet iemand hoe luchtballonnen bestuurd worden ten opzicht van de omringende luchtstroming? naar mijn weten kan dit alleen door hoogteverandering plaatsvinden. De ballon komt in een andere stroming terecht en verandert daardoor van richting. Maar kan een luchtballon ook van richting veranderen ten opzichte van de huidige stroming door krachtsuitoefening op de stroming? bv: kan dit door een zeiltje tussen ballon en mand? kan dit door de externe stuwkracht? kan dit door vormverandering van de ballon?

of kan een ballon tenopzichte van de stroming zich totaal niet zijwaarts verplaatsen?

als je een goed artikeltje weet, graag zou ik zeggen. alvast bedankt.

Arjan de Vries

In a few words manoevering is achieved by varying altitude.

The rotation of the earth produces a phenonomen called the Corealus <sp> effect, in the northern hemisphere the wind will veer with altitude, the reverse is true in the southern hemisphere.

If for example, in the northern hemisphere, the surface wind is directly from the south the balloon will track directly north - a track of 360 degrees. As altitude is gained the balloon will increasingly take a north north easterly track. The ammount of steerage varys from day to day and may vary between nothing and 90 degrees so the pilot will be checking the ammount of steerage as he climbs.

If a suitable landing site is spotted and it is left of the current track the pilot will slowly decrease altitude allowing the balloon to pick up the wind as it backs nearer to the surface. If the landing site is dead ahead then altitude is mainted and a rapid descent made when the balloon is over the spot. And if the landing spot is to the right of the current track then height will gained to steer right before descending.

Height is controlled by either heating the balloon or allowing it to cool by less frequent burning. There is also a rope in the balloon which via a pulley system will open a hole in the top of the balloon which can be used to dump air and initiate a fast descent - after a suitable ammount of air is dumped the hole reseals!