I noticed that Jeppesen includes additional runway information on their 10-9 or 10-9A charts. Are these listed values consistent with FAA runway declared distances?
- What does the runway distance mean under "Additional Runway Information" on Jeppesen plates?
- What are Runway Declared Distances?
- How do pilots use stopway, EMAS, clearway and displaced threshold?
- How do runway declared distances affect my takeoff distance?
Jeppesen uses its own method to calculate additional runway information. They have been providing additional runway information long before the FAA started providing declared distances and are fairly accurate but there is some discrepancies pilots using Jeppesen products need to be aware of.
Analysis of the two runway distance providers show Jeppesen's takeoff value is very close to the FAA's TORA value. Jeppesen's landing beyond threshold value is the same value as the FAA's LDA value.
The two values that Jeppesen does not provide information for is TODA and ASDA.
- TORA: Takeoff runway available
- TODA: Takeoff distance available
- ASDA: Accelerate-stop distance available
- LDA: Landing distance available
It is the ASDA value that will get multi-engine pilots in trouble. From the previous Q&As we learned that multi-engine pilots are required to ensure the airplane's accelerate-go distance is not greater than the TORA or TODA value (depending on whether or not their airplane can use a clearway for takeoff considerations) and their accelerate-stop distance must be lower than the ASDA value.
If these multi-engine pilots fail to reference applicable declared distance information they could potentially takeoff at a weight greater than allowed by their AFM and FAA regulations.
The FAA has developed a presentation talking about runway declared distances: http://www.faa.gov/tv/?mediaId=1132
How about examples:
Analyze the data and you will see that if multi-engine pilots only go by the takeoff distance on Jeppesen charts they could takeoff overweight. Jeppesen does not include ASDA values on their charts.
These pilots may conclude they can use the whole length of the runway for takeoff performance. If their takeoff distance is the runway length they will lose the runway safety area protections designed to keep them safe.
An email from Jeppesen concerning this oversight: After reading the email response below, it may not be a good idea to trust the runway information presented by Jeppesen.
Our Airport Diagram Charts are designed to be used for air navigation, flight procedures, and airport operations. They are not designed for aircraft performance planning. The distances contained in the Usable Lengths section of the Jeppesen Airport charts are informational and are not intended to be used for take-off and landing performance planning. These distances are provided on the charts to assist with the operational use of the runway. In order to comply with published declared distances, pilots need to reference take-off and landing performance planning data that is provided by either their own performance group, or another provider, such as Jeppesen’s OpsData service. OpsData provides on-demand runway take-off and landing performance analysis for airports worldwide, in part by analyzing, using, applying and presenting Airport Declared Distance data.
Another reason that the usable lengths are informational is that we do not revise our charts for all state source that we receive, we instead analyze that source and then revise charts based on our process criteria. What this means for the usable lengths is that we only process charts for changes in usable lengths when the change is greater than 200’. If the only change on a chart is the usable lengths and they are less than 200’, then we will make a note of the change and apply it to the chart when it is next revised sometime in a future revision. On the other hand, OpsData will update declared distances and re-run performance calculations whenever any of the lengths change by 25’ or more.
We don’t identify what the Usable Lengths should and shouldn’t be used for in the Airway Manual. Since the lengths are not intended to be used as declared distances, we have refrained from labeling them as such. That is why only some lengths are supplied and they are located under the heading ‘Usable Lengths’. The Introduction section defines the lengths we do supply and mentions that they are in regards to the physical runway length only (i.e. they don’t take into account any stopways, clearways, etc.).
AIM 4-3-6 provides the definitions of declared distances and where pilots can find them, which is the Chart Supplement (formerly the A/FD). For pilots that don’t have the availability of performance planning services, this would be where they could go to find that information.