RE: JetLegend F-16 (1/8) Testflight
There's something wrong. Mine would hold 120psi without any problems.
There is a pair of set screws that regulate the speed of Landing Gear vs door retraction/extension. You may have one fo those set screws too loose or something, therefore creating a leak. You should try spraying some water with soap to try to determine where the leak is coming from.