GMU Height Monitoring

A key component of RVSM implementation is monitoring of the altitude-keeping performance of aircraft that have received their RVSM Airworthiness Approval.  Altitude monitoring can be accomplished by either trained technicians using a portable GPS-based Monitoring Unit (GMUs) or by flying over a ground-based monitoring system (AGHME).  The data required for verification can be collected on either a scheduled flight or a dedicated special flight test.

AeroMech can assist with the FAA-mandated altitude monitoring requirement by dispatching a trained technician to perform an on-aircraft GMU test.  A typical monitoring flight will take no more than two hours and consist of approximately 30 minutes of data collection at an RVSM altitude (FL290-FL410).

AeroMech is one of few companies that have recently acquired the Enhanced2 GPS-Monitoring Unit (E2GMU). This new equipment was developed using the latest GPS receiver technology, ensuring a successful flight test.

Please contact AeroMech if you require monitoring services at

FAA Monitoring Approvals can be found through the following links.