On 10/6/2005 10:51, Ron Garret wrote:
In article ,
Mark Hansen wrote:
On 10/6/2005 08:23, Ron Garret wrote:
In article ,
Ron Rosenfeld wrote:
OK, so say you're flying AVX V21 SLI FUL. Fullerton ATIS says the VOR-A
is in use. Then you lose comm. What would you do and why?
Being more familiar with Jepp charts, and having to rely on NACO charts for
that approach, perhaps I am missing some subtlety.
But assuming a non-emergency situation, not getting into the discussion of
what to do at SLI if you're ahead of your ETA, and also assuming IMC, I
would maintain the V21 MEA of 4000' until reaching SLI. At SLI I would
execute a racetrack type procedure turn on the SE side of the final
approach course, descending to 2600'. Passing SLI inbound I would cross
BWALT at or above 1500' and then continue my descent to the MDA and land if
I met the requirements of 91.175 and the runway were clear.
As to why? I would do that because that's how that SIAP is charted
No, it isn't. There is no "racetrack type procedure turn" on the chart.
There is a hold that is part of the missed approach. And if you fly
that hold so as to end up at SLI inbound then you've flown it in the
wrong direction.
I think Ron said he wasn't as familiar with the government charts.
There are two Rons in play here :-) Ron G. (that's me) is looking at a
government chart.
Thanks, but I wasn't confused about that. ;-)
However, if you look at the chart, the procedure turn is indicated
with the Barb, pointing 155 degrees. You can see, also, that if you
use AIBAS IAF, no procedure turn is necessary.
True, but you're not coming from ALBAS. You're coming in on V21.
My point was that *if you were using ALBAS*, you would not need the
procedure turn. According to the SIAP, if you're using the VOR as
the IAF, you would need to use the procedure turn.
(As
an aside, doesn't it make intuitive sense that, from a TERPS point of
view, if no procedure turn is required from ALBAS that none should be
required coming from V21?)
Victor 21 is not a feeder route for the approach. If it was, it would
be charted as such. So you may be able to argue your point with the
procedure designers...
When you hit the VOR, you turn outbound for the procedure turn, 200
degrees. During the outbound leg (and the procedure turn) you can
begin your descent to 2600'. You should time it such that you are
at 2600' before you get back to the VOR.
Note that you need to remain within 10NM of the VOR during the turn,
so you can go outbound quite a log way (to aid in the descent) before
actually beginning the physical turn.
I presume you mean turn to a 200 heading, not turn 200 degrees.
Yes, you can because I said "Turn, 200 degrees" instead of "turn 200 degrees",
which wouldn't make any sense anyway...
Sorry it wasn't clear.
V21 is
on a 202 heading. You would be turning 178 degrees or 182 degrees
depending on which way you made the turn. Now...
Right, because V21 is not a feeder route...
Do you really turn to a 200 heading, or do you turn to intercept the SLI
200 radial? Those are not the same maneuver.
You intercept the radial, of course...
Do you turn left or right and why?
You turn toward the protected side of the procedure area, which is to
the southeast.
At what point are you "established on the outbound leg", when you reach
a 200 heading, or when you are established on the SLI 200 radial?
I'll bet you can answer that one yourself ;-)
Finally, suppose you flew this Byzantine procedure... by the time you
got to the actual procedure turn (which, I note in passing, would be
your SECOND course reversal) you would be in almost exactly the same
spot as you were just minutes ago when you were on V21. Why is it safe
to descend now but not then?
What is the MEA on the victor airway (I don't have it here...) Something
like 4000'? They aren't going to change the MEA of the airway just to
satisfy an approach (or at least they didn't in this case). So, you'll
be approaching the VOR at 4000' ... much to high to begin the approach.
Now if you look at the feeder route from AIBAS, it has a minimum
altitude of 2600'. This is exactly what you want. If you don't want
to do the PT, use this IAF rather than the VOR.
Note that WILMA requires a PT because it is not aligned within 30
degrees of the FAC...
Now, if they created a fix somewhere out on V21, and wrote a feeder
route from that fix, then you could. Effectively, you've be flying
V21 to the fix, then initiating the SIAP from there. However, they
didn't, so you can't ;-)
That gets in to why the designers set up the approach this way, which
I don't know. As a pilot using the procedure, I need only to interpret
the chart. I don't really have to understand the "whys" behind it.
rg
--
Mark Hansen, PP-ASEL, Instrument Airplane
Sacramento, CA
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