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What altitude does the "Apt Elev" on the Jeppesen charts represent? According to my research, the height we call "airport elevation" indicates the highest altitude on the landing surface at the airport. I think that what is meant by the landing surface is the runways. In the chart given below, we see that the "Apt Elev" height is higher than the highest runway threshold altitude. When this is the case, I think that the highest point on the runway is not at the end of the runway and at the beginning of the runway, but in this case, can there be curved runways with the highest point in the middle? As a result, I sometimes see that "Airport Elevation" is given higher or lower than the highest runway threshold heights on some charts. Is it because the definition isn't correct or is it because I'm missing something? I'm also asking because I see the definitions are the same: Are "Field Elevation" and "Airport Elevation" the same thing?

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-Images from LTCN Jeppesen charts-

Also about definitions: enter image description here enter image description here

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  • $\begingroup$ I don't have a reference so I will not make this an answer yet. But LTCN has a 1.2% rwy gradient, which is not an insignificant uphill slope when using rwy 07. The fact that the apt elev is 14 feet higher than the departure end elev just means that there is an extremely slight downhill slope (14 ft) somewhere between the rwy thresholds that otherwise slope uphill (when using rwy 7). 14 ft over a rwy length of 7546 ft is quite minor. $\endgroup$
    – user22445
    Commented Apr 8, 2023 at 0:47
  • $\begingroup$ What you mean is that the runway has a wavy structure rather than a straight one? So the runway can be vertically curved? $\endgroup$
    – pilot162
    Commented Apr 8, 2023 at 12:41
  • $\begingroup$ That is what it seems to be. The amount of gradient is about 1.2% (excluding the extra 14 ft shown by the apt elev) by my calculation. LTCN does not show the point on the runway where the apt elev of 1724 ft. is located. Do you agree? $\endgroup$
    – user22445
    Commented Apr 8, 2023 at 18:14
  • $\begingroup$ I agree with what you said. Then I answer the question by saying that the height value, which we call airport elevation, is the highest point on the runway. $\endgroup$
    – pilot162
    Commented Apr 9, 2023 at 15:09

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So this is right in my line of work. The discrepancies you see may be indicative of sloped runway profiles (with the higher elevation being in the middle). More likely however, it’s because not every country follows the ICAO recommendation for reporting airport elevation.

Jeppesen publishes what the host nation publishes for airport elevation, regardless of whether that meets the standard, ICAO/FAA definition (i.e., the highest elevation of a landing surface). Japan is a good example of this. To Japan’s credit, they mention this exception in their AIP, GEN section 1.7.

There are other examples where a nation will publish the runway profile elevations but then list a different (higher) airport elevation. They are clearly not following the ICAO standard. I recently saw this where the field elevation was at the airport reference point (ARP), but that ARP was not on a landing surface. It was located on a former, permanently closed runway.

Of note, you should never seen an airport elevation lower than any published elevation for a runway (threshold elevation, runway end elevation, midpoint elevation, etc.)

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  • $\begingroup$ Nice insights, and welcome to Av.SE! $\endgroup$
    – Ralph J ♦
    Commented Apr 10, 2023 at 1:40
  • $\begingroup$ Thank you so much! $\endgroup$
    – pilot162
    Commented Apr 10, 2023 at 14:12

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