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View Full Version : EHSI Heading vs track up.


screwdriver
27th Apr 2006, 09:13
What are the advantages of one display over the other?
Which is the more popular?

gas-chamber
27th Apr 2006, 22:31
Once you get used to it, you will probably find track up the better. After takeoff, unless on a radar heading, you want to establish track asap. If you suffer and engine failure on takeoff, you will find just flying the track number at the top of the EHSI will make for accurate control - try it in the simulator. The only reason I can think not to use track up is if your company SOP prevents it - in which case they should deactivate it to stop you being tempted towards its advantages...

john_tullamarine
27th Apr 2006, 23:05
Alternatively, those of us who like not to get too rusty on conventional presentations might choose to use HDG up normally and TR up for letdowns.. especially ILS.

XL5
28th Apr 2006, 01:31
Not getting rusty certainly does equate to regular switching between modes. TR up enroute and HDG up for the ILS with traditional 360 degree ILS presentation, that way the crosswind correction angle won't come as such as a shock during a low level breakout to the visual. Turning it all off and going raw data can also be interesting :ugh: .

john_tullamarine
28th Apr 2006, 03:45
.. one presumes that folk do a lot of raw data anyway ... lest the basic skills atrophy in toto ..

Centaurus
28th Apr 2006, 07:29
From conversations with airline pilots over the past 25 years I would say raw data (meaning no FD or autothrottle if you are serious) flying is rare. Seems from talking to first officers some captains are basically frightened of switching off the FD (perhaps "apprehensive" is a better term) and will refuse to even let the F/O practice a simple raw data climb or descent or approach - even in CAVOK. There is much lip service to the advisability of keeping current on raw data but that is all it is - lip service. Few seriously believe it. Part of the reluctance against raw data is loss of face if the instrument flying by the captain is let's say "rusty." If the F/O raw data is rusty the captain is free to criticise but it is a courageous (read foolhardy)F/O that laughs at the captain's raw data attempts. Company SOP rarely encourage raw data -the usual reason being we have paid millions for sophisticated FMS, so use 'em.

InTransit
28th Apr 2006, 07:31
You'll find HDG UP useful in the terminal area as ATC will give headings, not tracks when vectoring. However, trk is useful for (almost) everything else.

john_tullamarine
28th Apr 2006, 08:32
It is a point of regret that Centaurus is, very sadly, quite correct .. subject to a sensible assessment of workload and airspace environment, I loved nothing better than to fly the whole leg with no FD and no A/T (typically less than 90 minute sectors) in the 733 - and, if the sector suited, leave the FMS in the background and do it like a real aeroplane.

Probably just a reflection on my need to do the hard yards to keep my skills up (and they sure do disappear extremely rapidly if I am out of practice) .. but I could fly the sim to a 0/0 fullstop ILS with none of the bells and whistles .. great for the self esteem at the very least.

pilothouse
28th Apr 2006, 08:55
With track up, I could never get used to the life-threatening thunderstorm at 12 o'clock appearing apparently harmlessly well off to one side on the screen in any kind of crosswind.

Max Angle
28th Apr 2006, 11:22
On thw aircraft I have flown (737 and Airbus) you don't get a choice, on the Boeing it was pin selectable by the airline who set track and on the Airbus it's heading whether you like it or not. Having used both I think heading is a far better presentation. Much better to have the top of map matching the nose of the aircraft, makes the wx radar and TCAS displays relate to your eye view.