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Aspen, CO KASE, looking southeast 150 degrees.
Boyne Mountain, MI KBFA, aerial view of the Boyne Ski Resort.
the departure end of the runway (DER). Unlike ODPs and SIDs, the OEI obstacle fight path starts its obstacle assess- ment when the aircraft reaches 35 feet above the runway, using a portion of the runway for obstacle clearance. Another difference is that the OEI must account for “low close-in obstacles” that are not required for climb gradients in ODPs and SIDs.
For a contract trip to Toluca, Mexico, with a Fortune 500 company, the director of aviation asked if I would review the OEI procedures and run some numbers as this was their first time flying to this destination with an airport altitude of 8,466 feet. I did that and test-flew the procedures with an engine failure in a flight simulator at the charted maximum takeoff weights and temperatures. Not everyone has access to a fourteen-million-dollar simulator to test-fly
their upcoming trips. Still, I was lucky to be able to back up the information provided by APG.
The APG data and the simulator practice with engine failures at V1 confirmed that we could take off with up to 14,000 pounds of fuel, up to 21 degrees F. It was interesting to observe the rising terrain while I flew up the valley, per the engine out procedure, with a negligible but adequate single-engine climb rate. When it did come time for the actual departure from Toluca MMTO Airport, the tempera- ture was a few degrees cooler, and we only needed 13,000 pounds of fuel. Both engines kept running fortuitously, so the climb out was much better than I encountered during my simulated test flights.
The goal is to find an OEI departure procedure that mir- rors the normal ODP or SID you are f lying. This pre-planning eliminates a lot of busy work during an emergency engine failure. Most operators, including training companies such as FlightSafety and CAE, recommend loading the FMS, briefing your normal SID/departure, and loading the one- engine inoperative departure into the secondary flight plan. If you lose an engine on takeoff, all you or your co-pilot, if you have one, must do is activate the secondary flight plan. Some pilots “split the boxes” or un-synchronize the FMS boxes to separate the all-engine versus the OEI procedure. The problem with that technique is that you must re-sync the FMS CDUs after every takeoff without an engine failure, significantly increasing the chance of an error due to being heads down during a busy time.
The more complex the OEI procedure becomes, it’s usually rewarded by an increased maximum takeoff weight (see analyses chart above). The more complex track follows the
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