The time limit for. shipping a POV is the same as for travel and HHG transportation limits (JTR Para 5366, POV. Transportation Time Limitation), 1 year from the date of retirement/separation with severance. pay or 180 days from the date of separation.
The envelope is the large bag that holds the helium gas. The envelope is generally cigar-shaped, for aerodynamic purposes, and made of a durable, airtight, lightweight fabric (polyester composites) that is much like the fabric of a space suit.
Objects that float in â¦the air, such as balloons, blimps, Other uses of helium include: - being a protective shield while growing silicon and germanium crystals. - supersonic wind tunnels - nuclear reactors - a protective shield for titanium and zirconium fabrication. - pressurizing liquid fuel rockets.