McConnell AFB 3D Prints a Custom Funnel for KC-46 Engine Servicing

The maintenance problem was simple

Tech. Sgt. Brandon Branstetter, a crew chief with the 22nd Aircraft Maintenance Squadron at McConnell Air Force Base, looked at the KC-46A Pegasus engine starter service routine and saw a turkey baster. Technicians were using a makeshift funnel to add oil, and it was dripping onto the hangar floor.

He could not find a commercial product that matched the shape and maneuverability needed for the job. So he built one.

From CAD to printed part in-house

Branstetter measured the dimensions, modeled the part in CAD, and printed the first prototype on a Bambu Lab H2D. He tested several materials before settling on TPU. The final funnel resists oil and fuel, so it will not break down after repeated use.

The geometry was tricky. The funnel had to reach across a specific gap while staying angled enough to direct fluid into the engine starter. That specificity meant no off-the-shelf tool could do the job.

Cost and logistics

Test versions printed in PLA cost about 30 cents each. The finished TPU funnel runs two to three dollars to produce in-house. The base concluded that buying a commercial alternative would cost more and still would not meet the exact design requirements.

The same process could spread to other maintenance tasks across the base. Branstetter noted that almost any repair job can benefit from 3D printing when the alternative is waiting on a supplier or forcing a mismatched tool.

Why this matters

The U.S. military is expanding on-site additive manufacturing to solve exactly these kinds of problems. Legacy parts disappear from catalogs, and field repairs cannot wait for supply chains. McConnell's Innovation Lab joins a growing network of base-level 3D printing facilities that turn maintenance delays into same-day fixes.