Stabilized Approaches - A Question

[Two's in]

Often watch the arrivals/departures at an international airport in central Florida (the one that isn't SFB) and it raised a question about stabilized approaches. With southerly operations to the eastern parallel runways, departing runway is usually 17R, arrivals 17L and I frequently observe arrivals switching from 17L to 17R within about 2 miles of the threshold, clearly having been given a late clearance, and with the obvious advantage of about 2 miles less taxying to the gates. This always appears to be done in solid VMC conditions, no aerobatics or dramatic arrivals, but it appears to be the same airlines doing it - ie. the LCC's. Never see a Speedbird or Vermin doing it, but then again, there's probably more scope for doing it in a 737/717 than something bigger. The question is, do these carriers have Operating Procedures that acommodate more latitude with stabilized approaches with a view to ultimately reducing operating costs, is it always the PIC's decision, or something else? Probably less scope for this in Europe where parallel runway ops are unusual as opposed to over here where it is routine.

[taildrag]

last minute runway changes

I was an F-100 F/O for now-defunct Midway Airlines. Once, flying VMC into our home base RDU (Raleig Durham, North Carolina ) we were issued 6 (SIX!) runway changes on the same approach, which I believe must be a world's record.

Finally gave up head- down fiddling with the FMS, and landed using ILS and VASI glidepath guidance.

[Dan Winterland]

It happens sometimes at some airports in the US. The official term is a 'sidestep approach' and it is a recognised procedure. I once did an approach which was sidestepped three times at LAX - all 4 parallel runways and this was with one of the aforementioned Brit carriers. If you have a requirement to be stabilised by a certain height, obviously this isn't going to work. Some lattitude is required.

[alexban]

In VMC you should be stabilized on approach at 500' agl,compared to 1000' on IFR flight.
parallel aproaches are normaly done in Europe also,in most major airports.There are some conditions stipulated by the CAA regarding for ex distance between the two rwys,but it's done here also.

[jondc9]

Hi

somehow I think this is Orlando airport ( Kmco). I've been there often and I don't like flying to florida. Whenever I went to Florida there were always thunderstorms to worry about. I wasn't senior enough to fly there when the weather was good.

a couple of points.

2miles from the runway on glideslope one would be about 640' above field/touchdown zone elevation. about 320 feet for every nautical mile for glideslope.

That is starting to get a little low, but dooable for the 500' rule that another poster mentioned.


It is also possible your estimate of distance is a bit off. If the runways are close together ( less than 2500' or so apart) the shift of runways isn't too bad. If it is a couple of miles that is a bit much at low altitude, so please re-evaluate the distance/altitude. AT 3 miles you are almost 1000' and it is much easier to change.

Also, a pilot may have requested and is expecting the runway change and be ready to execute the change.

Also a pilot may decline the change in runway for many reasons. INCLUDING the fact that most pilots get paid by the minute and wouldn't mind an extra 5 minutes of taxiing.

I recall declining a change at low altitude and was surprised at the rudeness of the controller. However, if said controller had been good he would have respected my decision. If not good, why would I care?

a pilot usually briefs one approach, good pilots who are familiar with airport quirks might also say, " we will plan to change to runway x if offered and above x altitude.".


I've been shifted on runways many times and just said NO.

jon

[standbyils]

When considering low level runway changes ask yourself "does the potential gain justify the potential risk?". My answer has always been "No". ATC often think they are doing us a favour (shortened taxy) - depends how you look at it I guess.