Re: Korean Air 801 crashed on approach to Guam

Date:         29 Aug 97 00:53:43 
From:         Phil Wood <>
Organization: AeroMarketing Associates (
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  or MIME structure wrote:

> > Just how important is it to a landing in darkness with little or no
> > visibility ?
> not too important, since the G/S only gives guidance coupled to the A/P. If
> the G/S is inop, there are 'manual' slopes used of approx 3 degrees.

Not true - The GS information appears on the the pilot's instrument
panel - He can either couple or handfly the GS (and LOC) - If the GS is
inop, the approach usually reverts to a LOCalizer only which has fixed
step-downs at either time or distance intervals.  See the Jepp approach
chart at

> > How common is it for the glide slope to be inoperational for airports
> > that handle 747s on a daily basis ? Is this a no-brainer for pilots when
> > it is missing, or does this require a lot more attention ?
> there are enough reasons to have the G/S tramsitter inop. It's not a big
> deal. if the weather requires the G/S and it's not working... the runway is
> closed for landing.

Your statement that the "weather requires the GS" is confusing - I think
you mean the weather is below LOC mins (304 feet in this case), then the
aircraft can not commence an approach.  True for Part 121 (airlines) and
135 (charters), but not true for Part 91 (private) aircraft - They can
attempt an approach down to the 304 feet and if they can make out the
airport environment, go ahead and land.

With respect to the Guam approach, the NOTAM'd GS still left a LOC and a
VOR approach available to the pilot - Either would have offered a safe
approach had the aircraft remained on the approach ...

     Phil Wood                        
     <a href = "">Phil Wood</a>