Airship sets altitude record in stratosphere

[archiebald]

From the Yomiuri Shimbun

A giant dirigible launched from Hitachi Port in Hitachi, Ibaraki Prefecture, early Monday morning for a test flight into the stratosphere reached the highest altitude ever achieved by such an airship.

The test flight was a step toward bringing the Stratosphere Platform, a communications and earth observation base, closer to being a reality.

The airship, which was developed by the Education, Science and Technology Ministry's National Aerospace Laboratory (NAL) at a cost of 600 million yen, is 47 meters long, has a diameter of 12 meters as its widest point and weighs 500 kilograms.

It was made from Vectran, a super-light, high-performance thermoplastic multifilament yarn that gives the aircraft 20 times the buoyancy in air of conventional airships, enabling it to float in the low-density atmosphere of the stratosphere.

At 3:21 a.m., with strobe lights flashing, the helium-filled airship rose as if being drawn up into the starry sky. It flew for about 70 minutes and reached an altitude of 16,400 meters.

At 5:15 a.m., after gathering samples for measuring the concentration of greenhouse gases in the atmosphere, the airship's hull burst open and helium gas escaped, bringing the airship down in the waters 40 kilometers east of the port.

The concept of the Stratosphere Platform being advanced by the Education, Science and Technology Ministry and the Public Management Ministry is of a 250-meter-long airship that floats at an altitude of 20,000 meters. The ministries plan to use it for high-precision aerial photography and as a low-power communications satellite.

Compared with satellites put into orbit by rocket, the platform has the advantage of costing little and requiring little energy.

The NAL is planning next year to test a 60-meter-long propeller-driven airship equipped with instruments for observation and communications at an altitude of 4,000 meters.

[Mentor]

all well and good, but of limited use and a probable hazard to aircraft (remember barrage ballons? ), it can`t stay up that long anyway since even mylar allows helium or hydrogen through, so the thing would need re-inflating every few days or so.

Mentor.

[Astronuc]

What about mylar with a near atomic layer of Al on the inside and outside.  We used to use 'aluminized' mylar in radiation detectors.

Also, one could do a mixture of H2/He.  IIRC, He gets out quicker because it is smaller than the H2 molecule.