Fantastic presentation very clear, thank you. I just wondered why they were so few likes, then I realised the video was only 1 hour old! The printer is working this very moment to print out your guide.
@ClearFlight1
7 ай бұрын
Thank you! I'll be doing Part 2 next week
@HypoxicWaiter
3 ай бұрын
Great video. Do we not change the gate by the value of single drift?
@ClearFlight1
3 ай бұрын
Hi! Yes, strictly speaking the gate should be adjusted by single drift. However, some schools teach this and some don't. The gate is really just an approximate indication of your position in the hold, rather than a perfect science. So we've left it out of this presentation, which is designed to give you a good basic understanding before heading into your flight training. Your individual flight school will teach you the specifics of how they want you to fly the hold. Hope that helps!
@Rodhern
7 ай бұрын
A word about strong headwinds on the outbound leg. I will use an exaggerated example to present my point. Assume there is a 30 kts headwind aloft on the outbound leg (there certainly can be). Assume that we fly the hold at an approach or loitering speed of 90 kts TAS (not very realistic, but it makes for a nice example). So for the holding diagram shown the wind is 09030KT. Now consider two outbound timing examples. The rule of thumb says to add 1 sec for each knot. This example is exaggerated, so let us be extra cautious. We add 40 secs to the outbound timing. During the first turn, for one minute, we are moved 0.5NM west. Then during 1:40 outbound with ground speed 60 kts (90 minus 30) we move 1.67NM east. During the turn to inbound track we move 0.5NM west again. This leaves an inbound track of 0.67NM, which at 120 kts ground speed (90 plus 30) is 20 secs. The beauty of this example is that the time for a trip around the pattern totals four minutes (1:00 + 1:40 + 1:00 + 0:20). Say I aim for the standard one minute inbound leg flight time. In this case I will extend the outbound leg timing to three minutes. Let us run through the pattern timings. First turn is 1:00 and moves us 0.5NM west. Outbound for 3:00 moves us 3.0NM east. Second turn is again 1:00 and moves us 0.5NM west. The inbound leg becomes 2.0NM, which takes one minute to fly (at the 120 kts ground speed). The morale of the story is, if you have a strong headwind on the outbound leg, do not cut your outbound travel short, or you might get quite rushed on the inbound leg. In the examples above if you use a strict 1:30 outbound timing, you get 15 secs on the inbound leg. That is not a lot (e.g. if you need to reintercept an inbound track). Also notice from the second timing example, that 30 knots led to a 120 secs increase; that is a 4 secs per knot ratio! What would you do in such a situation? I think it might make sense to see if you can choose a faster speed, but let us say you cannot, how much time would you add to the outbound leg?
@ClearFlight1
7 ай бұрын
Hi, a valid point raised! 2 considerations for your scenario: 1. The hold timing is not required to be 4 minutes. Although it still gets referred to as a "4 minute hold", that hasn't been a requirement for at least 2 decades and I'm not sure when (or in which countries) it was a requirement before then. The 4 minute (nil-wind) hold is really just used as an example for students who are first learning the theory of the hold. ICAO PANS-OPS Doc 8168 simply tells us to adjust the outbound time of 1 minute to account for the wind. It does not tell us how to do that. So you are within your rights to make the outbound timing 3 minutes if you wish, provided you do not leave the hold protected area. 2. The same ICAO doc also tells us to start the outbound timing at the abeam position or wings level, whichever comes later. So in your example, you would finish the outbound turn 0.5nm west of the abeam position. You would then fly straight and level for 30 seconds (at a 60 knot ground speed) before reaching the abeam position, where you would start the 1:30 outbound timing. That would give you 2:00 on the outbound leg in total and is halfway between your two examples. Personally, I would fly the 1:30 outbound time, which starts at the abeam position, but that is not the only way it could be flown. Your example of 3:00 outbound would be another valid technique in those circumstances. Some schools that use slower aircraft teach an outbound time of 1 minute +/- 1.5 seconds per knot of HW/TW to compensate for this. As with almost everything in aviation, there is more than one solution to the problem!
@Rodhern
7 ай бұрын
@@ClearFlight1 Ahh, yes, of course, the abeam position rule is what saves the day. Completely slipped my mind. Thank you.
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