Forum: F-16 Procedures

Question for the engineers out there: Does stowing the radar for landing protect it in some way?

There is a WOM that stowing the radar before landing will prolong its life or prevent damage during touchdown of the aircraft. It is not listed as a procedure in any manual (that I've seen) but many pilots are adamant. My belief is that the FCR withstands up to 9 Gs and functions with no problems; the most Gs conceivable on landing would be less than 3 Gs if you land the jet like a Navy pilot. :) Most proponents of stowing claim there is an issue in "G-onset" during landing; i.e. the rate of increasing force. I don't buy it. Whether you slowly or quickly apply 2 Gs, it is still just 2 Gs.

F-16.net Sponsor

Well, the FCR antenna while energized certainly possesses the capability to maintain the array in whatever position it is currently at. Turning off the radar will put it into the stowed position which will certainly lock it into place, but it is still being held there by the AZ and EL servo motors. I know of no directive, policy, rule of thumb, or other information that would support a claim that putting the radar into OVRD or STBY prior to landing prolongs the life.

Now, there was (and still is from time to time) an issue where (under certain circumstances and dependent upon individual aircraft construction) the FCR interfered with ILS glideslope reception, and caused the ILS symbology to appear invalid on the HUD. Guidance to select STBY or OVRD is still in the Dash One today. Nose radomes were modified to add a one-inch piece of foil tape in front of the ILS antenna to correct the problem. Unfortunately, not all radomes have been modified, so this guidance is still valid.

That may be one reason why pilots stow the FCR antenna on landing.

Best Regards,

Could it have anything to do with making sure the folks in de-arm are able to have offspring?

OL

The radar goes to STBY once you get weight on wheels, so they would not get any more radiation than anyone else that's subjected to the radar on final. Only reason I've ever heard of for going OVRD befor landing is as JoeSambor says if it makes the glideslope unreliable. One other time would be during a formation landing as wingman so you're not "tingling" your lead...

Thanks - I had never heard about the ILS interference before, at least in any of the blocks that I've flown. The proponents say the FCR should be in OVRD for all landings to avoid damaging it. Certainly stowing it to avoid setting off lead's RWR is a valid technique, but I prefer just turning down my volume.

The information about ILS interference is in a Note near the beginning of Sec 7 of the flight manual.

Quote:

The proponents say the FCR should be in OVRD for all landings to avoid damaging it.

I'd say the proponents are wrong. In all my years reviewing and coordinating reviews of what went into the flight manual for technical accuracy, I don't ever recall such a suggestion, either from the engineers responsible for integration of the radar or from the field. If it was indeed a damage or life cycle concern, I expect it would have been mentioned officially long ago.

Funny what people will believe without a shred of evidence.

Best Regards,

Forum: F-16 Procedures

FCR in override for landing