26 June 2025
CubCrafters has announced the public release of its long-standing Supplemental Type Certificate (STC) that increases the certified gross weight of the Piper PA-18 Super Cub from 1,750 lb to 2,300 lb — more than 30% boost in payload.
Although the STC was first developed in 2007 and updated in 2012 as part of CubCrafters’ internal work on the company’s FAA-certified Top Cub, this is the first time the upgrade is being offered to the broader public.
“This STC was a critical part of our internal certification programme for the Top Cub almost two decades ago,” said Brad Damm, CubCrafters Vice President.
“Given the increasing demand for performance enhancements in legacy Super Cubs, we believe the time is right to make this valuable capability more easily available.”
CubCrafters President and CEO Patrick Horgan added, “We’re committed to giving classic aircraft like the Super Cub new life by applying engineering solutions that significantly enhance performance, safety, and mission capability.”
Piper Super Cub with the 30% higher payload thanks to the mod
The gross weight increase will be attractive to bush pilots, floatplane operators, and those flying in remote or rugged environments, where every extra pound counts.
On float-equipped aircraft in particular, the higher payload makes it more feasible to carry two people, full fuel, and luggage.
However, the upgrade doesn’t come without extensive airframe work. To qualify for the 2,300 lb gross weight, aircraft must undergo major structural upgrades, including new wings, landing gear, and a stronger engine mount.
An engine with at least 180hp is required, along with aerodynamic enhancements such as tail strakes and vortex generators. The result is a modernised Super Cub that retains its classic feel while offering improved capability and safety.
The STC is available either as part of a full aircraft overhaul through the CubCrafters factory in Yakima, Washington State, or as a parts and certification package for approved third-party maintainers and rebuilders.
Johnny McKinney, the company’s Aircraft Maintenance Services Manager, the upgrade complements many popular STCs already found on Super Cubs.
“Our customers will often incorporate modern avionics, a constant-speed propeller, tundra tyres, or a belly pod as part of their overhaul project — all of which are compatible with the 2,300 lb configuration.”
