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The definition for the Threshold Crossing Height is, according to the sources that I have checked, "the theoretical height above the runway threshold at which the aircraft's glideslope antenna would be if the aircraft maintains the trajectory established by the mean ILS glideslope or MLS glidepath" (source). FAA's Aeronautical Information Manual states:

5-4-23 Threshold Crossing Height (TCH) has been traditionally used in “precision” approaches as the height of the glide slope above threshold. With publication of LNAV/VNAV minimums and RNAV descent angles, including graphically depicted descent profiles, TCH also applies to the height of the “descent angle,” or glidepath, at the threshold. Unless otherwise required for larger type aircraft which may be using the IAP, the typical TCH is 30 to 50 feet

Since every runway seems to have its individual pair of TCHs values (one for each Displaced Threshold), I was wondering if there is any similar "Threshold Crossing Height" value that indicates the optimal height above DER (Departure End of the Runway), for each of a runway's thresholds. Does in the case of a departure the "35 feet above DER" rule apply to every runway?

Vector Zita
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    Closely related, perhaps a dupe? – Pondlife Aug 09 '18 at 15:33
  • @Pondlife Thank you for your comment, the question you quoted indeed indirectly provides an answer to my own question, since it confirms that the "35 feet above DER" rule applies (with some exceptions) for all runways. The difference is that the questioner takes this rule for granted. I am practically asking if a runway can have custom standards, as with TCH (which I understand now it is not correct), so for this reason I feel that the question is (subtly) different. If you re-post your comment as an answer, I will mark it as the accepted one. – Vector Zita Aug 11 '18 at 16:20

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