Cockpit crews don’t always consider all their options during takeoff planning, according to Steve Leon, a member of NBAA’s Domestic Operations Committee and a former United Airlines pilot. “Have you ever declined a Standard Instrument Departure [SID], or reduced takeoff weight, because the aircraft wouldn’t meet the required climb gradient in poor weather, if one engine becomes inoperative [OEI]?” he asks rhetorically in an article posted on NBAA’s website.
Leon thinks too many flights are canceled needlessly as a result of a lack of understanding of a few takeoff-planning basics that he and he committee outline in the article. “Because of the variability of AFM aircraft performance charts, TERPS and departure charting requirements and limitations, Part 25 aircraft certification requirements, and difficulty in obtaining obstacle information in the takeoff path, the ability for pilots to determine exact flight paths and takeoff weights is problematic,” Leon said. And when in doubt, he said, most pilots wait for better weather or chop payload and fuel to improve performance.
For Part 91 takeoffs, unlike Part 135, the FAA requires only that pilots have a procedure in mind in case an engine quits. “A number of vendors create [useful] alternative procedures, but the FAA has no good method of showing those takeoff procedures to pilots,” Leon said. “Pilots simply don’t know there are any other options as they attempt to strike the right balance between safety and maximum performance.”
The article, “One Engine Inoperative Takeoff Planning and Climb Performance,” reminds pilots that they are not required to fly an assigned SID after an engine failure. That means they are also not required to maintain the minimum climb gradient on that assigned SID in an emergency. They only need to plan how they’ll avoid obstacles in their path with an engine shut down. AC 120-91 is the guiding document for Airport Obstacle Analysis, but Leon said, “It almost takes a genius to figure out what it’s trying to tell you.”