# Reply to post: Re: LOHAN On Top?

### LOHAN ideas..

#### Re: LOHAN On Top?

Couple of problems with this idea. First, is the net going to be non-stretch or will it stretch with the balloon? If it's non-stretch then how are you going to keep it aligned so that the LOHAN remains perched on top of the balloon whilst the net is loose and baggy at low altitudes? If it's stretchy then it's really no different to the skin of the balloon (you wouldn't want the net to restrict the expansion of the balloon because it needs to expand, to maintain lift by reducing its density as the outside air pressure drops - if this didn't happen i.e. the balloon kept the same volume as it ascended it would reach a point where its density (mass per unit volume) equalled that of the thinning air outside it - result = no more lift. By letting the balloon expand, its density continues dropping, keeping it below the density of the air in which it floats).

Second is that the avionics package isn't rigidly coupled to the balloon, so with the weight of LOHAN on top, it'll still tip over. In fact , this scheme results in least stability when everything is vertically aligned and will only become stable once the balloon/LOHAN combo has tilted over.

"Aha," I hear you say "what if we mount LOHAN sideways so that as the balloon tips over it's then pointing upwards?" Well, not a bad idea, if you can guarantee which way it all tilts - it could tilt the other way so that LOHAN is pointing downwards instead of upwards.

A very long rigid pole, with the electronics package at the bottom and LOHAN on the top, and with the cluster of balloons to lift the entire ensemble being attached close to the top, would work but when you factor in the enlargement of the balloons and the need to make sure that they don't wrap around LOHAN as they expand, you're looking at a _very_ long pole (Wikipedia says that weather balloons can typically expand by a factor of 100 before they burst - it's unclear whether that refers to volume or size though).

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