With ForeFlight’s introduction of Takeoff and Landing Performance in version 11.4, it’s a good time to revisit your Pilot Operating Handbook (POH) and get reacquainted with the runway performance data in it. It’s important to understand that the runway performance results provided by ForeFlight are based on the published data in the POH. ForeFlight’s calculations are only as good as the data provided by your aircraft’s POH. Since we support aircraft models spanning multiple decades, POH data content and variation is large.
Take, for example, single-engine Cessna pistons. Looking at Section 5 (Performance) of the POH, you will see the takeoff and landing distance tables provided are titled Short Field, meaning the short field takeoff and landing techniques need to be applied to achieve the published distance numbers. This often involves rotating or approaching at a slightly slower airspeed, often with non-zero flap setting.
But many of us take off and land using the Normal procedure, outlined in Section 4 of the POH. The Normal procedure often advises different (faster) speeds and with flaps up. But few POHs provide any guidance on how takeoff or landing distances change when using the Normal procedure vs the Short Field procedure. When using one of these aircraft, it is critical to be aware that you are seeing Short Field distances in the ForeFlight results, which are shorter than what you will experience if you fly the Normal procedure takeoff and landing.
To help you recognize this, ForeFlight adds a “(Short Field)” note after the Flaps setting under Aircraft Configuration when using an aircraft that only provides Short Field distances. You can also review our list of Takeoff & Landing Performance supported aircraft here to see which ones only provide Short Field distances.
Another factor you must consider is the lack of certain corrections. Many piston POHs do not provide runway slope or non-paved runway corrections to the distances. All data are published for paved and level runways, which is what ForeFlight uses. Even though ForeFlight provides a user-adjustable runway slope input, changing this value does not affect the resulting distances. This is because such POHs lacks correction values for the runway slope.
It’s a great time to pull out the POH and study its runway performance section closely, so you know exactly what ForeFlight’s takeoff and landing results mean for your own aircraft’s performance.