Why is it that some ILS approaches take you into the ground prematurely? My most recent account of this happening was at JFK airport. I had NAV1 dialed in to the ILS (runway 4L), good weather, speed was around 180IAS (in the 747), full flaps, A/P on, A/T on.
Intercepted the ILS signal fine (HDG light went out), plane lined up nicely with the runway. Followed the glide slope down to where the marker was centered in my display (VS and HLD lights went out as expected), but then the plane continued to descend below the glide slope (A/P and A/T were still engaged), and of course I ended up being on the news that night.
As you can tell from my many posts about landing, it's not one of my best skills. What the heck am I doing wrong??
You can refer to my posts on ILS Approach to IAD. I can repeat what I said. I am flying a 737-400. I am appoaching KIAD. What I did was APR with A/P engaged but disengaged the A/T. Iseemed to have more control. I to was on the news several occations for landing short of the runway. Dang those lawsuits get expensive.
Hope this helped.
Another good point to watch out for is your speed. In a 747 if you're under max-landing weight, you'll probably only need an airspeed of about 150-160 with full flaps. The reference speed (found in the kneeboard) is the best speed to make when you're intercepting / holding the glideslope. Any higher and both you and the computer will have to take too much of a nose down pitch to land at the runway (probably why the computer had trouble landing it), and any lower and you'll probably stall! 😉
There just seems to be something wrong with the A/P in the 747. I can usually land the 737s fine. In the 747, sometimes all the lights go out (HDG, VS, and ALT) as soon as I press the APP button (sometimes as far out as 35 miles). Other times, the A/P crashes me short of the runway. And then of course, sometimes (rarely) it works like it's supposed to. And then there's the dreaded disengaging of the A/P, which makes the plane buck up and down like a rodeo bronc.
I think there may be some programming flaws with the A/P in the 747. I've tried everything I can think of. I created my own livery for the 747, and I'm so frustrated that I'm about ready to put my copy of FS2004 on eBay.
Nothing should be this difficult.