Built Before First Flight. Still Holding at Altitude.

An aircraft runs on more than its engine. Fuel has to get to the engine. Hydraulics move the landing gear. Brakes need lines that hold under pressure every time. The pitot-static system feeds the instruments that tell the pilot how fast and how high. None of it is optional, and none of it gets a second chance once the aircraft is in the air.

On this build, all of it was fabricated, assembled, and pressure tested. Fuel lines, hydraulic lines, brake lines, pitot-static lines, and the oil lines off the PT6 turbine. Rigid and flexible. Start to finish.

For anyone who knows fluid systems, the rigid lines were built across several aluminum alloys depending on what each line needed to do. 5052, 6061, and 2024 covered fuel, oil, and the hydraulic lines running at moderate pressure, each alloy chosen for the balance of strength and workability the application called for, with 2024 being the stiffest of the three to flare by hand. For the brake lines and the higher-pressure hydraulics, 304 stainless, the standard for systems where the margin for failure doesn’t exist. The pitot-static lines, carrying low-pressure instrument signals rather than fluid under load, used semi-rigid Poly-Flo and Nylo-Seal tubing with brass push-to-connect fittings, the standard for pneumatic instrument lines where flexibility and clean routing matter more than pressure capacity.

Every line was flared, fitted, and assembled to AN and MS fitting standards, the same fitting families used throughout aerospace fluid systems. Rigid where rigid made sense, flexible hose assemblies and semi-rigid poly lines where the application called for it.

Then every one of them got pressure tested. Not as a formality, as the actual proof. A line that looks right and is built right still has to hold pressure without leaking, without failure, under the conditions it’ll see in service. That’s not something you take on faith. You test it, you document it, and the result either holds or it doesn’t.

These held.

The aircraft those lines are in is flying. Every fuel, hydraulic, brake, pneumatic, and oil line, built and tested before it ever left the ground, and proven since.

The same thing applies anywhere fluid lines have to work. Not just aircraft. Fitting selection, alloy choice, pressure testing. Whether it’s an aircraft, hydraulic equipment, or an industrial fluid system, the process is the same and the standard doesn’t change. If a line has to hold pressure, it gets built and tested like one that has to.

That’s the standard for fluid systems work, same as anything else. It doesn’t matter how good it looks going together. It matters whether it holds when it’s actually doing its job.

Parallax Manufacturing. A different angle on what a machine shop can be.

If your application needs lines that hold, get in touch.