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Guest Claude troncy

Some question about DH DA and hydraulic

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Bonjour,I am studying the documentation before using FS2Crew and I have some questions.1 I did not find in the doc how the landing field elevation is set(may be this is missing) .Before posting I made a search and found the answer in this forum2 Page 43 , we have to turn on the hydraulic to be able to set the trim.I think it is done with the demand pump selector, but why do we have to use both pumps as it seems that only the left system provide hydraulic to the trim ?3 I am a bit confused about DA and DH.In CAT I it is said that DH is not used and the reference is barometric, but in the doc , we can read Decision height, shouldn't it be Decision Altitude (DA)I understand that with non precision approach we use MDA.In which case do we use DH (reference to radio altimeter). In page 72 there is a NO DH CAT 3B APPROACH profile, it seems to have RA calls.What is the signification of the word NO before DH.Is this profile modelised in FS2Crew ?Sorry but I didn't find the answer in the doc.May be my problem is that I want to understand how it works by reading the doc before trying the product !!!!Best regards Claude

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Hello Claude.1. FO sets landing elevation.2. Dave indicated that he turns them all on. When turning them on, work right to left, when turning them off, work left to right. This prevent fluid transfer between the systems.3. What page on the manual is that so I can look? CAT I uses DA CAT II and greater use DH (though in the audio briefs the Capt will still refer to DA as DH so as to avoid possible confusion with any possible MDA).4. No DH = No Decision Height. Yes, this profile is modelled in FS2Crew. It's the Monitored Approach. Hope that helps,Bryan

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Hi BryanThank you for your quick answer.3 Page 36. But may be I didn't understand quite well.I thought that the low drag noise ils profile was a cat 1. in fact it could be a cat 2 or 3 and in this case do we have to set the DH and use the RA for the calls or as you write page 36 "item 1 How to fly .." do we have to bug the da on the altimeter and use the baro altimeter for the calls.As you see it is not quite clear for me. Thanks for your helpclaude

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Hello Claude,To bug DA for a CATI ILS, set the bug on the altimeter to the DA. Example: if the DA is 450 feet, set the Alt bug to 450 feet.There are special calls for CAT II or CATIII approaches that are built into the the Monitored Approach profile, and which vary depending on the DH selected.Basically, if you want to do a CAT II or CATIII selected "MONIT" approach for the Approach type on the Approach Briefing page and use Monitored Approach procedures.There are additional calls used on CAT II/III approaches that are not built into a the standard Low Drag/Noise profile.Hope that makes sense,Bryan

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Hello Bryan,MerciJust to be sure.If I want to make a CAT II or III ILS approach as a PF, I select MONIT, I set DH , but do not pass the control to the F/O.Am I right ?Claude

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Hello Claude,If the weather is so ugly that you have to do a CAT II or III, then you would typically use Monitored Approach procedures, and you must accordingly pass control to the FO. The FO becomes the PF, and he will fly the plane through the autopilot.Now, if you want to cheat a bit and do it your own way so to speak, you can still do CAT II or III using FS2Crew and remain the PF. Just select the "Low Drag/Noise"profile and set the DA to what the DH would be.Now it won't be 100 percent technically accurate in terms of the calls if you do it that way, etc., but it'll still basically work.Chees,Bryan

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On this same subject...What happens when the altimeter needs to be set for a DA above 1,000? I do not see anything on the altimeter to tell me, for example, whether I have the orange bug set at 200ft or 1,200 ft. Does it make a difference to FS2Crew or does it just know the difference?Damon

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Hello Damon,If the DA is 1200 feet, set the altimeter bug to 200 feet.FS2Crew looks at the arrival runway elevation via the FMC to do the appropriate math in cases where the DA is greater than 999 feet.Cheers,Bryan

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