This question is not aimed at any particular model of aircraft. I would like to know if DME indications during an MLS approach are received through the TACAN or by a seperate internal MLS component. Thanks.

TACAN isn't part of the MLS hardware. There is a DME transmitter (DME/P actually) collocated with the azimuth transmitter. Section 6.7 of 11-217 will answer all your MLS questions.

https://www.e-publishing.af.mil/pubfiles/af...man11-217v1.pdf

6.7.6. MLS Precision Distance Measuring Equipment (DME/P). The MLS DME/P functions in the same way as the DME described in the TACAN section of this manual. DME/P accuracy within 7 NM of the station has been improved to be consistent with the accuracy provided by the MLS azimuth and elevation stations. The DME/P is an integral part of the MLS.

[ 02. August 2006, 19:51: Message edited by: BC ]

Thanks for the information.

The MLS was designed to be a self-contained (DME included), cheap, and portable precision approach NAVAID. They figured it would be huge and all airports would eventually have one. This was before the ILS was the standard and places like DFW, SFO, etc. were the only places you were likely to find one.

So most airports started installing ILSs because they're more reliable and rendered the MLS useless with the expection of sporadic military use.

HD

[ 02. August 2006, 20:44: Message edited by: HerkDerka ]

Weren't those supposed to be used on LZ's? I thought that was why the military had them.

Originally posted by Mambo:

Weren't those supposed to be used on LZ's? I thought that was why the military had them.

There are MMLS systems, Mobile MLS.

Originally posted by Mambo:

Weren't those supposed to be used on LZ's?

I have no idea. MLS is like TACAN, it was designed by the military to be used at FOB airfields as a cheap, transportable navaid.

HD

Another relic of the Cold War Eastern-bloc invasion plan and its associated tools.

We have two MMLS's in my STS unit. We have set them up all over OEF/OIF. Personally, if I can't carry it on my back, I don't want it. It's an intermediate-AZ/LZ NAVAID, not meant to be a first-there asset.

I know the range, how to ID the thing, the defualt modes, why not to put the thing in manual mode, where to look for the warning flags if I lose the signal, some queep numbers on the elevation and azmuith ranges, where the antennas are in my airplane, how far off it can be non-computed, and the two places they put them...

But, I've never actually flown an appraoch on one.

Now that I think about it, I've never had anyone ask any one of those numbers, more less mention an MLS. What a waste of brain bytes.

Thanks Little Rock!

But, the answer I've been told is the one Mambo gave. Although, he may have been the one that said that, who knows.

H3Nav? Did someone piss in your wheaties recently asking you about MLS shit that you didn't know? That's pretty brutal.

BENDY

[ 03. August 2006, 09:28: Message edited by: Bender ]

MMLS was going to be our way in to all the FOBs in obscure parts of the world, but then something else happened...everybody got GPS and uses that for approaches. Cheap and works everywhere. Like SATCOM said, they can still throw it up and suddenly there's an IFR approach (for everybody with an MLS receiver). But not many places to train on it -- although if you have trouble flying a precision approach, you have bigger issues.

Originally posted by dmeg130:

MMLS was going to be our way in to all the FOBs in obscure parts of the world, but then something else happened...everybody got GPS and uses that for approaches. Cheap and works everywhere.

Isn't there a remote possibility that the GPS system could go offline?

If so, it wouldn't hurt to still be trained on a self-sustaining, portable precision approach system, right?

I'm not sure about other's, but in the past year I've had to fly an MLS approach during a checkride (annual instrument/qual) and on a REC ride prior to my operational mission evaluation. So while MLS's aren't used much, Pilots' of aircraft that have the required equipment should have a basic knowledge of how to fly them.

A peek is worth a thousand cross-checks.

Batman

[ 07. August 2006, 17:25: Message edited by: Batman ]

Every time I try to fly the damn thing at LRF on a pro sortie I always back it up with the ILS because the damn thing isn't notam'd out but it never works, and the one at DYS did the same thing to me on my Qual Check.

Like NDB's I wish they would just go away!!!

cheers folks

I guess you could always duct tape a Hot Pocket to the nose... At least you'd get some use out of the thing then!