How far off a PAR is too far?

[NorthSouth]

How far do you have to be off the centreline on a PAR approach before you get told to go around?
NS

[anotherthing]

When you're no longer on the PAR tube in Azimuth???

Otherwise I'd have thought it would be if you reach MDH/MDA/MAP and are not visual...

[Lurking123]

Scratching my senile head a bit, but I don't think you will ever be instructed to "go around". Setting aside the lack of clearance, ISTR that the following phraseology (military but I don't recollect any civilian PARs) would be used by ATC if they lost radar contact:

"C/S I have lost radar contact, maintain heading and height, acknowledge"

"Are you visual with the aerodrome"

in the event of a "negative" answer

"C/S execute missed approach procedure...."

I may be wrong. The last talkdown I gave was in 1989. :eek: You would merrily fly off the side of my picture if you were somewhere between 7-10 degrees off the centreline, dependant upon the relative position of the radar to the runway.

PS. ATC would never tell you to go around for failing to be visual at DH/DA; that's most definitely pilot stuff.

[anotherthing]

Lurking - totally correct... ISTR that phraseology as well...

as for the go around if not visual at MDH/MDA - it is entirely the pilots call, not ATC and is an automatic action as soon as MDA/MDH is hit, if not visual. The only ATC input is calling out approaching MDH and at MDH.

(been a while since I did any talkdowns as well)

[ATCO Fred]

as for the go around if not visual at MDH/MDA - it is entirely the pilots call, not ATC and is an automatic action as soon as MDA/MDH is hit, if not visual. The only ATC input is calling out approaching MDH and at MDH.

:8..don't forget PAR is a precision approach aid so its DH/DA; MDH/MDA are for non-precision approaches SRA, TACAN etc...

[Monkey Madness]

I don't think there are any hard rules as to where is too far, but as a rule of thumb we were taught that if the a/c was not slightly L/R or on C/L by the 2nm point then the supervisor would encourage you to so better next time - by way of a ruler round the back of the head! :E

[NorthSouth]

Thanks guys, all useful, but I wasn't thinking of a situation where the aircraft is near DH/DA; I was thinking of the scenario with a student pilot doing their first PAR and making a real mess of it; let's say they're handed to Talkdown on a closing heading at 7nm and are given a heading adjustment to get on the centreline but miserably fail and start heading off the centreline with no apparent correction. At what point does the controller say "radar service terminated", "execute the missed approach" or whatever?

What I'm really trying to get at is, on ILS approaches there's a clear and well-established criterion - if you go beyond half-scale needle deflection you go around. But is there any controller equivalent criterion for a PAR?

NS

[whowhenwhy]

If it was me and it was early in the approach and the guy seemed not to be flying the heading that he was given, I'd ask him to confirm heading such and such degrees and if it didn't add up, I'd tell him that I suspected an "un-serviceable" compass or gyro and to adopt the no compass, no gyro procedure. Of course, if it was a PA28 at the end of the tube ......:suspect: Would they know what to do??:confused:

[Gulfstreamaviator]

I loved my trips into Northolt in days gone by, PAR for controller training, was always offered.

We would then try very hard to make them work extra hard, speed increses, just as we got settled.

Many beers exchanged on the ground......

Who provided this service any more, I dont think I will get the chance to drop in to Northolt again, bit big, the aircraft not me....

glf