moving a localizer to another runway?

[AdamZ]

Can an airport move a localizer from runway to runway? Listen to the KLM audio on this site around 4:15 or so they say they are switching the localizer.

 

[Let'sgoflying!]

I think I heard they can electronically flip it to the reciprocal runway but not to a whole other piece of concrete

 

[Teller1900]

I don't know where the clip is, but my guess would be just what Dave said...they're just flipping the signal to the reciprocal runway; at least that's what's always been going on when I hear "expect delay vectors while we switch the localizer," or something along those lines.

 

[KennyFlys]

Could there be localizer arrays on more than one runway but allow only one active at any given time? The remaining arrays are shut down. That's my guess.

 

[flyingcheesehead]

Can an airport move a localizer from runway to runway? Listen to the KLM audio on this site around 4:15 or so they say they are switching the localizer.

Adam,

If there are localizers/ILSs on both ends of a runway, only one can be turned on at a time.

5. Where a complete ILS system is installed on each end of a runway; (i.e., the approach end of Runway 4 and the approach end of Runway 22) the ILS systems are not in service simultaneously.

Overnight at KMSN, the tag that ATC records for the end of the AWOS goes something like "Madison tower hours of operation are from 6 AM to 11 PM local time. Common traffic advisory frequency is 119.3 and is monitored by crash, fire and rescue. For IFR clearances on the ground contact Chicago Center on 135.45. ILS 18 and 21 are selected."

So, presumably the folks in the tower choose whether the south or north one is more likely to be needed overnight, flip the switch, and go home.

 

[KennyFlys]

Kent's explanation is a given. I took Adam's question to mean there were two separate strips they were "switching" for localizer use.

I couldn't look it up. Nothing popped for "KLM."

 

[flyingcheesehead]

Kent's explanation is a given. I took Adam's question to mean there were two separate strips they were "switching" for localizer use.

What the heck would that mean?

I couldn't look it up. Nothing popped for "KLM."

The three-letter airport ID's cannot begin with a K or a W. I'm guessing it was just a typo from Adam's home field of KLOM. But, as KLOM doen't have any approaches except GPS, it must have been on Philly Approach or something??

 

[Graueradler]

I haven't checked lately but Fort Smith (KFSM) used to have a switchable ILS on 7/25. Since it could be received well beyond the field and the extended centerline of 25 passed over the airport my plane used to be based at (H35), I've used it for guidance between airports. Depending on which way it was switched, it would either be direct or reverse indicating. Before I realized what was going on, I thought my avionics was messed up. I was only looking at the approach plate for 25 and didn't realize that at times I was getting the "back course" for 7

 

[HPNPilot1200]

The tower uses an ILS interlock unit to select the current ILS equipment configuration. In many facilities, the TRACON can remotely switch the ILS signal to the reciprocal runway with the snap of a finger. Obviously this is the only way that ensures proper front course guidance (the correct inbound course) and identifier is transmitting.

This picture below displays the ILS remote status and interlock unit at PHL ATCT. ILS interlock is made via a different unit installed in the cab.

 

[KennyFlys]

What the heck would that mean?

Intersecting runways or possibly parallel runways too close for simultaneous approaches.

 

[AdamZ]

What the heck would that mean?



The three-letter airport ID's cannot begin with a K or a W. I'm guessing it was just a typo from Adam's home field of KLOM. But, as KLOM doen't have any approaches except GPS, it must have been on Philly Approach or something??

No actually I did mean KLM. I was referring to a audio of a KLM flight that declared a fuel emergency and had to land at Syracuse because Toronto was closed due to that plane that ran off the runway.

 

[flyingcheesehead]

No actually I did mean KLM. I was referring to a audio of a KLM flight that declared a fuel emergency and had to land at Syracuse because Toronto was closed due to that plane that ran off the runway.

Aha! And sho'nuff, Syracuse has ILS's on both 10 and 28.

 

[TMetzinger]

Could there be localizer arrays on more than one runway but allow only one active at any given time? The remaining arrays are shut down. That's my guess.

Ken's got it right - when you have two localizers sharing a common frequency for the same runway, they can switch one or the other set off.

 

[flyingcheesehead]

Ken's got it right - when you have two localizers sharing a common frequency for the same runway, they can switch one or the other set off.

Tim,

They don't even have to share a frequency. Lance Fisher might be able to tell us an electrical reason why, but they don't ever have active front-course localizers on both ends of the same runway. At MSN, we have ILS's on 18, 36 and 21. The 21 ILS can be on all the time, but only one of the 18/36 ones can be on.