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Old July 14th 07, 06:33 PM posted to rec.aviation.ifr
Viperdoc
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Posts: 155
Default Hardest approach flown so far

Yes, I looked at and could have chosen that approach. However, how often
does one get to fly a DME arc loc BC approach in a non-radar environment? I
was not necessarily looking for what was easier, and this particular
approach offered a lot of interesting challenges.

The gear in my plane, which is also KI equipped, definitely simplified the
matter, but it was still a challenge and learning experience.

"q" wrote in message ...
Viperdoc wrote:
Basically, it's as I initially said. We were at 13,000 and then were
cleared to intercept the arc from the SW. I was still descending while
trying to fly the arc, and then intercepted the final approach course
while still in the descent.

So, it was descending at a pretty rapid rate, turning to intercept the
BC, turbulence, and ice. I do have WAAS GPS as well as traditional DME,
which made some of it easier, but did not couple the autopilot, and hand
flew instead. (The DME fixes on the GPS may not necessarily be the same
as the DME from the navaid.)

I made very sure that I stayed on the final approach course, and did not
get low (which never happened due to the circumstances). Again, it is a
non radar environment, so the tower was asking for DME readouts.

The second WAAS GPS was set for the terrain page, as added information.


Monday Morning quarterbacking:

1. You had the latest and greatest RNAV package available.

2. The RNAV Runway 9 IAP has an MDA 520 feet lower than the LOC DME (BACK
CRS)-C.

3. The back course approach doesn't have straight-in minimums even though
it is lineup up exactly with the runway. That means the descent gradient
is excessive for straight-in minimums. In fact, the descent gradient is
very high; 635 feet per mile from the FAF to the runway at threshold
crossing height.

4. The descent on the RNAV Runway 9 is 3.46 degrees from the FAF. as shown
on the chart; or just less than 370 feet per mile.

5. Because the LOC BC approach does not have straight-in minimums you can
do a 360 once clear of clouds, but you need approval from the tower to do
that. It would have to be done at not less than 5120 and north of course,
and within the circling maneuvering area.

The RNAV 9 would have been my choice, given your equipment, then the tower
would be obligated to make reference to that procedure.

Unless you insist on the RNAV 9 they will always use the back course
because it makes life easier for them (they have all those DME distances
to make you report. ;-)