HI ILS Approaches
08-09-2012 | 10:43 PM
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HI ILS Approaches
I understand that "HI" approaches are intended for high-performance military aircraft to conserve fuel in the arrival/approach segment by minimizing their time at low altitudes.
However, I have noticed that decent rates prior to glideslope intercept on HI ILS approaches clearly exceed a 3 degree decent path, which would imply that the glideslope is intercepted from above. Is this actually the case? Seeing that you have false glideslopes at 9 and 15 degrees you're almost guaranteed to encounter them at such a high decent rate so close to the antenna.
However, I have noticed that decent rates prior to glideslope intercept on HI ILS approaches clearly exceed a 3 degree decent path, which would imply that the glideslope is intercepted from above. Is this actually the case? Seeing that you have false glideslopes at 9 and 15 degrees you're almost guaranteed to encounter them at such a high decent rate so close to the antenna.
08-10-2012 | 12:10 AM
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The high portion, like you said is just a means of getting high/fast jets into the terminal area and on the approach in a more expeditious and efficient manner. From about 8 miles in however, it's just a normal ILS. If you're intercepting glideslope at 5 miles from full high, you're probably dorked up.
08-24-2012 | 06:35 AM
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From: A319/320 FO
You will see anywhere from 5 to 7 degree descent gradients inside the IAF prior to the FAF (maybe more). As Grumble said, once you approach the FAF (hopefully at FAF altitude) you will intercept the GS from below and it is a normal approach.
10-08-2012 | 04:12 AM
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From: B737 Captain
Of note, the final approach segment, from the FAF to the runway, on a HI-ILS and the ILS for a given runway are the same. Sometimes we use the FA segment from the "HI" book because it provides additional information.
For example: at Lincoln (KLNK), the HI-ILS or LOC/DME RWY 36 publishes a DME to identify the FAF...whereas it does not in the ILS or LOC RWY 36 (LOM only...and that thing is down all the time). Good to know for a checkride to keep your shizzle squared and the winds in your favor.
For example: at Lincoln (KLNK), the HI-ILS or LOC/DME RWY 36 publishes a DME to identify the FAF...whereas it does not in the ILS or LOC RWY 36 (LOM only...and that thing is down all the time). Good to know for a checkride to keep your shizzle squared and the winds in your favor.
10-08-2012 | 12:27 PM
#5
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The others have nailed it. Also, of note, is that they are slowly going away. I think the FAA is trying to get rid of them, which really isn't a big deal as I don't think they are used all that much. I know I haven't shot a full Hi-approach since T-38s.
I also prefer the high approaches for their simplicity and not having all that excess information, that I don't need...
I also prefer the high approaches for their simplicity and not having all that excess information, that I don't need...
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