radarbeam
Posts: 998
Joined: Fri Mar 01, 2002 9:00 am

What Happened To The MLS (Microwave Landing Sys)?

Sat Jan 18, 2003 10:55 pm

Hey folks,

I've got a 1992 book at home about navigation instruments, it goes in great details about the ADF, VOR, RMI ...ect and there is even a small chapter on the MLS. Here's a quote from the book: "The ICAO decided that the MLS would start to replace the ILS in the year 2000".

So what ever happened to the MLS? AFAIK I've never heard of an airport being equipped by one. It does look like a good alternative for airport surrounded by terrain where an ILS can't be set up.

Thanks,
Radarbeam
 
buckfifty
Posts: 1278
Joined: Tue Oct 16, 2001 4:05 pm

RE: What Happened To The MLS (Microwave Landing Sy

Sun Jan 19, 2003 12:30 am

In '99 BA said they'd be the first airline to equip all their aircraft with MLS receiver units, pending the installation of a system at Heathrow. Haven't heard much about it since, though.

Just learned about this last week as part of my ATPL subjects. Apparently, fog affects operations at Heathrow up to 360 hours per year. It reduces operations to 22 movements per hour using CAT IIIB ILS, because of interference due to taxying aircraft affecting accuracy of the ILS system. With the implementation of MLS, it'll increase that number to 29, compared to about 42 movements per hour on a normal basis.

But I'd like to hear if anything's happened to that at all, it'll be interesting to see those approach plates...
 
flyf15
Posts: 6633
Joined: Tue May 18, 1999 11:10 am

RE: What Happened To The MLS (Microwave Landing Sys)?

Sun Jan 19, 2003 6:27 am

Last I herad, projected capabilities of future GPS systems would allow all of the capabilities that MLS would've without the very expensive equipment. I've never seen a real MLS approach plate, I'm not sure if one even exists.
 
Accidentally
Posts: 613
Joined: Sun Dec 10, 2000 7:33 am

RE: What Happened To The MLS (Microwave Landing Sys)?

Sun Jan 19, 2003 9:07 am

Indianapolis, IN
 
Woodreau
Posts: 1336
Joined: Mon Sep 24, 2001 6:44 am

RE: What Happened To The MLS (Microwave Landing Sys)?

Sun Jan 19, 2003 9:09 am

Chicago O'Hare used to have a MLS approach. I have seen the approach plate for it, but the approach (and the accompanying approach plate) has been deleted.

MLS was supposed to replace ILS, the capabilities of MLS over ILS were a 3D approach allowing multiple categories of aircraft to conduct the approach over different flight paths, versus the single straight in. It would also allow aircraft different glidepaths as well. MLS also included a data link which would give incoming aircraft runway status, weather, etc.

Development of MLS was further along in Europe than in the US. The FAA decided to abandon development of MLS after GPS arrived on scene, so MLS what few MLS approaches there are will be gone by 2010.

There is more info in the AIM. http://www1.faa.gov/atpubs/AIM/Chap1/aim0101.html#1-1-11

Cheers  Smile
Woodreau


Bonus animus sit, ab experientia. Quod salvatum fuerit de malis usu venit judicium.
 
buckfifty
Posts: 1278
Joined: Tue Oct 16, 2001 4:05 pm

RE: What Happened To The MLS (Microwave Landing Sy

Sun Jan 19, 2003 1:19 pm

But apparently, there are also problems with GPS systems development. In fact, the usage of ILS has been extended indefinitely by the FAA (originally to be phased out by 2010, along with a reduction of VOR aids), just because GPS aided precision approaches has proven not to be all that it's promised (DGPS apparently cannot cut the mustard in it's current form).

Until the U.S. Military decides to release encoding for the more accurate GPS, I don't think this situation will change at all. And knowing what the current political climate is out there, I don't think that's ever going to happen.

And from what I just heard, Heathrow is indeed putting in the MLS...
 
L-188
Posts: 29881
Joined: Wed Jul 07, 1999 11:27 am

RE: What Happened To The MLS (Microwave Landing Sys)?

Sun Jan 19, 2003 1:42 pm

GPS killed MLS.

That being said, The FAA as late as 1996 was installing MLS landing systems at airports. The money had been appropriated 10 years before but nobody cancelled the project. Those systems have now pretty much been retired due to nobody buying MLS equiptment.

What a waste of Tax Dollars.
OBAMA-WORST PRESIDENT EVER....Even SKOORB would be better.
 
PW4084
Posts: 287
Joined: Tue Mar 06, 2001 7:31 pm

RE: What Happened To The MLS (Microwave Landing Sys)?

Sun Jan 19, 2003 7:34 pm

MLS exists in military aviation, there's an MLS approach at KDYS and some strategic airlift have MLS capability (don't know about the other types).


PW4084



PS.......Buckfifty: I think the Department of Defense took away Selective Availability maybe a year or more ago. Can't remember the exact date.
 
avioniker
Posts: 1100
Joined: Tue Jan 01, 2002 5:38 am

RE: What Happened To The MLS (Microwave Landing Sys)?

Mon Jan 20, 2003 12:56 pm

The USAF was working on and developing MLS with the FAA and a couple of universities in 1979 and later, but the politics were overwhelming. Europe was developing a system with AEG Telefunken which, at the time, was vastly superior to ILS.
The system the US was fostering and trying to ram down everyone's throats was a Motorola based system using a significantly different frequency/pulse rate spectrum. The US government wanted their home based companies to be the prime vendors. The problems with the Motorola based system weren't overcome and never approached the AEG system before Honeywell and others got the ILS to be as accurate as the MLS was in 1990.
Therefore and voila, the US didn't continue, or contribute significantly to the MLS development as the ILS had become just as accurate as the MLS at that time. (Why develop new technology that wasn't any better than existing if it wasn't really needed?)
Oh yeah, GPS is a lot more accurate (potentially) than either (or will be whenever we figure out how to overcome that pesky 400millisecond lag).
One may educate the ignorance from the unknowing but stupid is forever. Boswell; ca: 1533
 
Illini_152
Posts: 959
Joined: Sun Jan 14, 2001 6:00 am

RE: What Happened To The MLS (Microwave Landing Sys)?

Mon Jan 20, 2003 5:20 pm

PW4084, they turned off SA back in 4th quarter of 1999. Now that WAAS is coming online, it's pretty pointless anyway.

- Mike
Happy contrails - I support B747Skipper and Jetguy
 
PW4084
Posts: 287
Joined: Tue Mar 06, 2001 7:31 pm

RE: What Happened To The MLS (Microwave Landing Sys)?

Mon Jan 20, 2003 8:22 pm

Thanks Mike, I didn't realize it has been that long. I do remember that the only real change in accuracy that I've noticed while using our Magellan Skynav 5000 (strictly VFR type stuff) since SA went away is that the altitude calculation seems much more accurate. Our lateral nav requirements aren't precise enough to notice a change. Obviously when it comes to precision approaches or bombs on target, the extra bit of accuracy makes a considerable difference.


Dan
 
jgore
Posts: 518
Joined: Sun Feb 17, 2002 2:41 am

RE: What Happened To The MLS (Microwave Landing Sys)?

Wed Jan 22, 2003 8:41 am

As far as I know, most aircraft carriers have MLS systems onboard because of the precision required while the ship is moving on.

Jgore  Smile
 
radarbeam
Posts: 998
Joined: Fri Mar 01, 2002 9:00 am

RE: What Happened To The MLS (Microwave Landing Sys)?

Wed Jan 22, 2003 10:12 am

Thank you guys for all the infos!

Radarbeam
 
gotAirbus
Posts: 791
Joined: Fri May 18, 2001 10:02 am

RE: What Happened To The MLS (Microwave Landing Sy

Thu Jan 23, 2003 7:08 am

Woodreau

MLS was supposed to replace ILS, the capabilities of MLS over ILS were a 3D approach allowing multiple categories of aircraft to conduct the approach over different flight paths, versus the single straight in. It would also allow aircraft different glidepaths as well. MLS also included a data link which would give incoming aircraft runway status, weather, etc.


Um...is it true that Kai Tak had this 3D navigational approach system (MLS) that help pilots guide their way into Runway 13 (the curved approach)?

(gotAirbus?)
(gotAIRBUS?) - (Got Commonality?) - (Have A Nice Flight!)
 
Trent_800
Posts: 136
Joined: Thu Jan 03, 2002 11:29 pm

RE: What Happened To The MLS (Microwave Landing Sys)?

Sat Jan 25, 2003 4:52 pm

Another problem with the MLS is the fact that, on approach everyone onboard started getting hotter and hotter  Smile/happy/getting dizzy Also the airlines couldent decide where to put the speaker that goes "PING" when the aircraft has come to a stop the the doors open.  Smile/happy/getting dizzy  Smile/happy/getting dizzy
Dan
 
muddydawg
Posts: 56
Joined: Fri Jan 17, 2003 10:17 am

RE: What Happened To The MLS (Microwave Landing Sys)?

Mon Jan 27, 2003 6:00 am

MLS exists on the C-17. I don't figure that they use it or it is so awesome it never breaks.
 
gotAirbus
Posts: 791
Joined: Fri May 18, 2001 10:02 am

RE: What Happened To The MLS (Microwave Landing Sy

Mon Jan 27, 2003 3:23 pm

Trent_800

Another problem with the MLS is the fact that, on approach everyone onboard started getting hotter and hotter. Also the airlines couldent decide where to put the speaker that goes "PING" when the aircraft has come to a stop the the doors open.
Dan


ROTFLOL! Where did you get your education from  Big thumbs up



Oh, and sorry, I thought MLS was implemented as airport radar...mistook it for something.

Please disregard my previous post

(gotAirbus?)
(gotAIRBUS?) - (Got Commonality?) - (Have A Nice Flight!)
 
L-188
Posts: 29881
Joined: Wed Jul 07, 1999 11:27 am

RE: What Happened To The MLS (Microwave Landing Sys)?

Mon Jan 27, 2003 5:58 pm

And there was that problem with the cats in the cargo hold.

They kept exploding everytime the damm thing was switched on.
OBAMA-WORST PRESIDENT EVER....Even SKOORB would be better.

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