A question for any MD11 or B717 Pilots?

[TotalBeginner]

I've noticed on the MCP that unlike boeing or airbus, there isn't a seperate button for LOC. The LOC and G/S can only be armed at the same time using the APPR/LAND button.

With that in mind, how do you track the LOC while performing say, a stepped descent without the G/S capturing before you've reached platform alt? The approach to RWY13 at Malaga being an example.

[DBate]

I don't have the charts for the approach into Malaga right now, but there are several possibilites:

Either use NAV or HDG mode for tracking inbound. On the other hand, there is no problem with arming the APPR/LAND mode if you are not on the 'platform alt'. The AP will capture the LOC, you can continue descent using LVL CHANGE or V/S as long as you don't capture the G/S from above. Should you come close to capturing the glide while still above 'platform alt', you have the option to increase V/S or to revert to the other modes I mentioned before (NAV or HDG).

The only time I really wished they had a LOC button installed is when flying a LOC approach.

Regards,
DBate

[TotalBeginner]

The only time I really wished they had a LOC button installed is when flying a LOC approach.

Provided you have absolutely no intention of capturing the G/S, or it simply isn't installed, I thought that there was a *LOC ONLY option on the NAV/RAD page of the FMC?

[DBate]

I thought that there was a *LOC ONLY option on the NAV/RAD page of the FMC?

Nope, not installed - and have never heard of that feature for the MD11.

[Capt Claret]

On the B717, that's the Douglas/Boeing 717, there's a * LOC Only option, line select key 5 left if memory serves, on the NAV/RAD page of the MCDU.

The option only appears if a LOC frequency is tuned.

[DBate]

@ Capt Claret

Thanks for that information. Obviously Douglas/Boeing did an improvement on that part of the FMC. Flying a LOC approach without a LOC ONLY option can be annoying.

[TotalBeginner]

On the B717, that's the Douglas/Boeing 717, there's a * LOC Only option, line select key 5 left if memory serves, on the NAV/RAD page of the MCDU.

Am I right in thinking that if this option is used, it cannot be cancelled to allow G/S capture?

[Capt Claret]

Am I right in thinking that if this option is used, it cannot be cancelled to allow G/S capture?

Not at all, simply press Approach/Land and the G/S is at your beck and call.

[davidaz68]

All md11s have the *LOC ONLY option on FMC rad nav page by default.
this item was there since maiden flight.
pushing this LSK arms loc mode. You don't need to push APPR/LND button on the flight control panel. If you do, LOC only mode is cancelled and full ILS capture mode is armed instead

[DBate]

All md11s have the *LOC ONLY option on FMC rad nav page by default. this item was there since maiden flight.

It is definately NOT correct, that ALL MD11 have the *LOC ONLY option on the FMC.
That might be valid for the ones that used to be operated by Alitalia (or their cargo subsidiary), but it is defintely not correct for the ones I am operating.

The *LOC ONLY option was optional when ordering the MD11, and not all operators chose to pay for that feature.
So please - no general statements...

Regards,
DBate

[maples]

md11 loc

I do not know if you got the answer yet, anyway there is an FMS loc only option on the app page.

Maples

[DBate]

Ok gentlemen,

I finally took a look at the manuals. In the chapter 'FMS' I found a list with all MD11 operators an their respective FMS options installed (so called FMS - Options Matrix). I tried to upload the picture, but that does not work - I just can post a link to a picture, unfortunatly I could not find the list on the internet (mods, any hint on that? ).

As I said before, the *LOC ONLY function is optional - airlines had to pay for it, and some operators chose not to do so (mine e.g.). davidaz68 and maples both seem to fly (or flew) the MD11 for Alitalia. They had/have the *LOC ONLY option installed. Others don't.

Consequently the passage 'FMS ILS Localizer Only' in the chapter 'Autoflight' of the OM-B states (first sentence):

If the LOC ONLY option is installed, ILS localizer control with disabled glideslope control is provided

So here is the overview (as of July 15, 2000, so there might have been changes)...

MD11 operators (past and present) which have the LOC ONLY option installed:

- American Airlines
- Finnair
- Korean Airlines
- Swissair
- Mitsui & Co., LTD.
- China Eastern Airlines
- Thai Airways
- Alitalia
- Federal Express
- Delta Airlines
- LTU International
- GATX Capital
- Martinair
- VASP
- Saudi Arabian Airlines
- City Bird

MD11 operators (past and present) which DO NOT have the LOC ONLY option installed:

- DAC
- GPA Group LTD.
- Garuda Joint Venture
- Varig Airlines
- China Airlines, LTD.
- International Lease Finance Corp.
- Japan Airlines
- KLM Royal Dutch Airlines
- Saudi Arabian Royal Flight
- Eva Airways
- P. T. Garuda Indonesia
- Lufthansa

Hope this helps.

Regards,
DBate

[davidaz68]

Thanks DBate.
In my manuals it was not listed as a company option.
One more thing to know.