ILS while not receiving markers

[Eric]

Is flying an ILS in a 172 while not receiving the marker beacons unsafe? If you've got the glideslope/localizer and altimeter, are the marker beacons just added situational awareness?

Maybe this thread should be in the 'I've never' section...

Thanks

 

[PTWOB]

No marker

As long as you are totally positive that you will never receive a false glideslope you can call it safe all you want. I wouldn't.

 

[hyper]

I don't understand why no markers have much to do with false glideslope determinations. As Eric guessed in his original question, markers are in fact another situational aid. they are in no way required for the approach. Look at the ILS12 at OPF for example, they don't even exist. Your approach plate tells you at what altitude you should be for glideslope intercept, and DH. That's all you need to determine if you are on the correct glidepath and what distance from the runway you are. Approach will give you a distance from the non-prec. faf when they clear you, and if you're conducting the approach in-communicado, you make sure that you are at your intercept altitude and established before intercepting from beneath as is required. Add in GPS, LORAN, or DME and the markers become very redundant. To say the approach is unsafe without them makes no sense at all.

 

[MetroSheriff]

Hyper,

Great post.

As long as you are totally positive that you will never receive a false glideslope you can call it safe all you want. I wouldn't.

PTWOB,

Unsafe??? Why wouldn't you?

By that logic, what do you have to ensure you are not receiving a "false" localizer signal?

Marker beacons are not a required component of the ILS. An IM is not even installed unless CAT II ILS is authorized. Marker beacons are not addressed as "inoperative components" of an ILS. Unless specifically noted for a particular approach absence of marker beacons or an OTS marker does not raise the MDA.

Reference the AIM 1-1-9 for further clarification.

 

[Anaconda]

so if you don't recieve the marker beacons in the mighty a320 you consider it unsafe? i'd be lying if i said i didn't even notice them 95% of the time. besides, they are on the endangered species list anyway...

 

[dsee8driver]

What' a marker beacon!?!?!

I have to admit, we don't really pay atention to them. Maybe in a CATIII approach tey are important but since we don't do any, half of the time they are turned down to minimum intensity. There are other ways to positively identify the approach fixes.



HYPER,

You mnetioned OPF. Are you from the Opa Locka area? That's where I learned to fly.

 

[MetroSheriff]

Marker Beacons

Oh No!!! What the hell is that BLUE Master Warning for????


Whoops never mind...forgot about those things.



In ATL aren't those things called "Turn To Assigned Departure Heading Initiation Points"???

 

[hyper]

dsee8driver,

Hey, no I'm not from there but I fly into OPF 5 nights a week.

Man, what a variety of planes, huh? I'd imagine it would be a networking dream.

Take care