T he Celtech A/M37T-21D Mobile Turboprop Engine Test Stand (METS) is accepted for use by the USAF, USN, Allies, Fleets & MROs for testing all series of the T56, AE2100, 501D, T53, PT6, CT7 and many other turboprop engines. Celtech is proud to produce this most widely used turboprop engine test stand in the world. The T-21D is your convenient “prop on” test stand. Thorough reviews of the T21 by Atec and Celtech since our 2013 merger have advanced many new improvements, while preserving compatibility and configuration. Modern upgrade models of many turboprop planes are supported for engine and propeller test by today’s T21D (METS). Now with Vital Link on our corporate team, Celtech can provide proven solutions for indoor T21 prop engine testing to USAF configuration. Our modern T21D is now configurable for prop-on testing of many additional turboprop engines, as shown in our listing below.