I've been practicing flying an ILS approach into Kansas City with the 707, and I keep seeming to engage G/S Auto at the incorrect time. There is a leg that runs about perpendicular to the approach which then reaches a fix with an altitude restriction of 4000 feet. The plane then must bank to 190° and descend to 2600', where the ILS feather begins (does that signify where the glideslope begins? I know I should probably know that, but nonetheless...). Where should I be engaging G/S Auto?

Thanks,
boeing247

Boeing247,

Have a look at the approach plate for 19R at KMCI

http://img594.imageshack.us/img594/3530/mciy.png

You picked a somewhat different approach since there is a note (*) in the profile box which defines when to track the glide slope.
In a regular approach where you would be level and drive up to the FAF (final approach fix - the Maltese Cross in this case, 2,600 feet) you could select altitude hold while being vectored or maneuvering to intercept the LOC. At that point, you can select G/S AUTO and arm the autopilot for an automatic capture of the LOC (first) and then the G/S. In G/S AUTO, you must intercept the LOC and be below the G/S intercept altitude. If you are above the G/S altitude, G/S AUTO will not intercept the G/S from above. G/S MAN will intercept both the LOC & G/S - RIGHT NOW - when you select G/S MAN whereas, G/S AUTO will remain on your last heading and altitude until the LOC comes alive. Generally, G/S MAN is only used when already established on LOC & G/S since it would be too rough on the poor passengers.  :P

Lou




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What I generally do is have one of the NAV numbers on the airport, and another on the ILS. Once I find the ILS, I cruise at about 2500 ft above sea level, and fly at a 90 degree of the runway. When the autopilot F/D is on G/S AUTO and so is the A/P, it should do the job for you.
Pete

Pete,

Letting the poor autopilot try and do a 90 degree intercept would cause this in the cabin...

http://img815.imageshack.us/img815/1893/puke.png

Sixties era equipment would not fair well. Try a more reasonable angle like 30 degrees.

Lou  ;)

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Panny wrote on Mar 16^th, 2012 at 5:14pm:

What I generally do is have one of the NAV numbers on the airport, and another on the ILS. Once I find the ILS, I cruise at about 2500 ft above sea level, and fly at a 90 degree of the runway. When the autopilot F/D is on G/S AUTO and so is the A/P, it should do the job for you. Pete

Are you sure you don't mean Above Ground Level (AGL)?

Mark

Thanks for the clarification, Lou. I was finally able to get it to intercept at 2600'.

Sorry my bad, AGL. If you are far away from the airport, the 90 degree intercept is not too bad. Plenty of time to align. Unless of course you are flying Kai Tak.