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Airbus Low Vis ILS Approach & Autoland

Interesting videos. I tried a "coupled GPS" approach a few time when I first installed FS9 some years ago. In a P-38! It worked pretty good. Not sure how auto-land systems work in today's airliners. Is it GPS? I know navy jets I worked on, even the A-7E, have (had) an auto-land system that uses ILS, auto-pilot, and data-link, where a radar system on the ship (SPN-42?) tracks the plane, data-links corrections to the plane, which uses the AP to issue commands to the flight control system. Automatic Carrier Landing System (ACLS). Even in 1985 it worked pretty good, according to the pilots I talked to about it. The system had several modes. One, where the ship just sent commands to the plane to position the "datalink bug" on the HUD, like ILS needles, and in "full auto" it would fly the plane "hands off" down to just before the round down.
 
Autoland uses either two or three coupled autopilots. The three autopilot system is called fail active, if one errors, the other two can continue. The ILS system must be CAT II-III certified and the critical interference area must be sterile. At a pre determined altitude (Radar alt) a flair maneuver is begun and throttles move to idle. The pilots are monitoring the instrumentation for flags or abnormal performance. In the 747 all we needed at a suitable airport was a 300 ft RVR. Flying one of those is slightly puckering as you never do see anything at all till the nose comes down and you get a short range view of some center line lights.

Cheers: T
 
fliger747 said:
Autoland uses either two or three coupled autopilots. The three autopilot system is called fail active, if one errors, the other two can continue. The ILS system must be CAT II-III certified and the critical interference area must be sterile. At a pre determined altitude (Radar alt) a flair maneuver is begun and throttles move to idle. The pilots are monitoring the instrumentation for flags or abnormal performance. In the 747 all we needed at a suitable airport was a 300 ft RVR. Flying one of those is slightly puckering as you never do see anything at all till the nose comes down and you get a short range view of some center line lights.

Cheers: T
Click to expand...

That would scare the pants off of me! How often is autoland used these days?
Ted
 
Fascinating + scary. "RVR" = ? Visual Reference?

Interesting such systems were in place as far back as the 1960s. I think the Vickers VC-10 had something like it. Dave Maltby's now ageing VC-10 model (FS9 + no vc (boo!) has a cool gauge that is simple to use and yes, does the flair on landing. My sense is, not being aware of many accidents attributed to the early auto-land systems, that they were not used much of the time?
 
expat said:
Fascinating + scary. "RVR" = ? Visual Reference?

Interesting such systems were in place as far back as the 1960s. I think the Vickers VC-10 had something like it. Dave Maltby's now ageing VC-10 model (FS9 + no vc (boo!) has a cool gauge that is simple to use and yes, does the flair on landing. My sense is, not being aware of many accidents attributed to the early auto-land systems, that they were not used much of the time?
Click to expand...

RVR- Runway Visual Range. I have watched these Low Vis Approaches/Autolandings with great fascination and when I saw the above video of the A320 doing it, I went and gave it a shot with the Aerosoft model(I had done it a few times before but not recently). The biggest negative with FSX is that you can't adjust the approach lights intensity levels and also, the landing light glare effect on clouds is something I have not seen replicated so far. In my video, you can see the taxiway lights pierce the clouds before you can see the runway lights. Under clearer conditions on that field, the approach lights raise hell!

It's been quite some time since I actually flew a real aircraft in IMC and shot ILS approaches under the hood(the last being at ILM and at MYR). It's an interesting experience being socked in and bounced around while getting a good case of the leans! I recall a quiet sigh of relief breaking out above minimums and seeing the runway approach lights. Can't imagine actually doing it as seen above!
 
Landing at 300 RVR you don't even get to see any approach lights. Most Cat IIIB landings are autolands. Some Cat II setups can be hand flown using a HUD. Many Asian airlines use autoland as standard practice. This was one of the reasons for the Asiana Crash at SFO, for some carriers a visual approach is truly an emergency procedure. A high standard of airmanship is required, more so as one doesn't get many cycles.

The Boeing system does a really good job of flying the airplane and is actually a great way to learn how the plane should be landed. It takes the amount of crosswind into account and makes several corrections in bank and crab making a final adjustment in the flare.

T
 
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