ILS 23 in BUF
 

SWAPA Pilots,

There is a potentially significant hazard concerning the ILS to runway 23 in BUF.

Information has been received indicating it is possible to obtain a significant nose pitch up, in some cases as much as 30 degrees, if the glide slope is allowed to capture before established on centerline. Pilots who are preparing to configure and land have the potential to experience abrupt pitch up, slow airspeed, and approach to stall if conditions present themselves in a certain manner.

This effect is the result of an earthen obstruction close enough to the ILS to affect the integrity of the glide slope signal. This has resulted in the issuance of an advisory given on ATIS which states that "the ILS Glide Slope for runway 23 is unusable beyond 5 degrees right of course."
When attempting to intercept the runway 23 ILS from right traffic, the ILS glide slope indication may read full deflection down. Just prior to intercept it may then move up in such as manner as to enable approach mode to capture in such a way as to result in a nose up pitch and loss of airspeed.

Southwest Airlines has issued a notice reading: "Until further notice, when executing the KBUF ILS/LOC Runway 23, DO NOT select Approach Mode until established on the localizer inbound."
This issue is being addressed on several levels in an attempt to address procedures, facilities, and communication regarding this matter. If you experience any issues related to this, please file an ASAP form and or call SWAPA Safety at SWAPA toll free.

WOw, I didn't even THINK about this happening. All the big talk on icing. I wonder if this happened and the icing just made things worse. This is a problem up in Duluth as well. We had a huge issue one day with severe pitch issues in icing conditions going down to minimums. We had to disconnect the AP after the first 2 huge oscillations. If we didn't disconnect as soon as we did we would have most certainly stalled.

You know, a few years ago and in VMC, I was flying into BUF intercepting the ILS below glidepath and my aircraft did pitch up as if to climb to intercept the glide path. I kicked off the AP and landed uneventfully. I did have at least 1 pax comment on the way out. The pitch up was that noticeable...hmm. This was circa 2005. I don't remember the rwy.

Interesting, thanks for sharing this info

Not shooting the messenger, but my BS flag goes up on this one...

A pile of dirt can bend a glideslope enough to have an autopilot pitch 30 degrees nose up to intercept? And this phenomenon is only 5 degrees off centerline?

If true, instead of MANPADS all the terrorists need is a bulldozer to push some dirt around and planes will be stalling and crashing all over the USA?

I think if this was the case we'd have seen more than a memo to SWA crews. Like maybe a NOTAM or something.

Just my .02

I'll contact the person who I got this from tomorrow, but I will say the ATIS in BUF mentions GS issues 5 degrees right of course on ILS 23

And the Colgan crew came in from the left for RWY-23.

As far as I can remember, the ATIS always broadcast that message. The memo mentions the pitch up when turning in from right traffic, but I am almost positive that Colgan would have made a left turn to intercept the course.

Beat me to it Tony

This actually seems like a reasonable concern.

Makes you go hmmm.

Anybody thought the a good upset could have had the seat slide back with the pilot holding it?

Had that happen more than once in a Cessna.