Wednesday, August 10, 2016

ILS is down. Localizer is up. And where is my DME?

Airplane: Piper Cherokee (PA-28-161/A)
Hobbs: 1.5 hours
Landings: 1

Flight Profile:

Clearance:
Cleared Oceanside Airport
After takeoff, Left turn 270 radar vectors OCN VOR
Climb and maintain 3000 expect 4000 10 minutes after departure
Frequency is 119.6
Squawk 5301

Flight Summary and Lessons Learned

The plan was to fly to OCN missed approach partial panel, then LOC/DME approach Carlsbad CRQ, then ILS Montgomery.
During ATIS prior to engine start, we found out that the ILS at Montgomery was down (for the next couple of days). We queried ground on 118.22 and found out that the localizer was up. So we planned on doing the LOC 28R approach into MYF after approaches to OCN and CRQ. 
We got into the system after takeoff and were told to go to 4000 and we stayed on 270 much longer than usual. During the flight up V23 (or thereabouts, we were told to fly direct to OCN VOR) we noticed there was a lot of traffic going into Oceanside. Eventually the controller we were with told us that there would be a 15 minute delay if we wanted to go to OCN and offered us the ILS to Carlsbad first. And we took it. We got vectored far to the east, but eventually flew the ILS, executed the missed approach, got back with ATC and we started our flight towards the LOC approach at MYF. OCN continued to be busy, so we contacted ATC and updated our plans to omit an approach at Oceanside.
Once the MYF localizer came alive on the nav radios, we noticed there was no DME coming in from the MYF localizer. I tuned the DME to the Julian VOR to see if we could get a read from it and we did. 
Localizer approach, KMYF RWY 28R
After a short while, I looked at my approach plate and noticed the IF (initial fix) at MIBBY was defined by the R-196 radial from Julian. I also looked at the plate and noticed that there was a chart that indicated time to the missed approach point from the FAF (Final Approach Fix). I decided to tune that radial but the problem was between this point on the approach and the FAF, how would I know when I could step down? I could have flown the highest known altitude from the IF to the FAF without any step downs (4200 is the MEA at MIBBY and the MEA at the FAF is 2500) but the descent would have been steep. Because at this point we were given a VFR practice approach, I decided that I could pull out my iphone and use ForeFlight. I overlaid on the sectional map the approach plate, and during the flight on the localizer, I was able to identify roughly where I was relative to various step down fixes.
This all worked fine except for the missed approach point is defined based on DME, which we did not have, or the time from FAF at 80 so knots, which I did not start timing and had to think about once on the ground. My instructor, and the fact we were on a practice approach, allowed us to get this far but by the time I was at the FAF, had this been a real flight, I would have been executing a missed approach. And, really, I can't use an iphone app to navigate. So, what in the end should have happened?

What Should Have Happened

Once we found out we had no DME, which we assumed was available given the localizer approach was up, we should have notified ATC. This hopefully would have led us to getting radar vectors, which were acceptable for this approach (position can be determined by radar or by DME). Whenever equipment for a flight that you expect to have for an IFR flight or approach (and especially if it is required for the approach or by FARs to perform the flight) becomes inoperable, it's time to tell ATC.  With radar position reports in lieu of DME, ATC, and then the tower, would have been able to tell me the critical points on the approach, including the missed approach point.  It would not have been as accurate as DME, but it would have gotten me in.
Of course, other possibilities would have been to go to an alternate, or ask for a visual approach, or given that the ceiling was unlimited and visibility was unlimited, we could have just canceled and flown in VFR (which really is what we were doing anyway given it was a practice approach). We missed out on an opportunity to see what it would have been like to fly with radar position reports probably because we didn't report DME out to ATC. Looking at the NOTAMS after the flight (see below), they advise that the ILS navigation is out of service, and do not mention explicitly that DME situated at the localizer is unavailable.

!MYF 08/010 MYF NAV ILS RWY 28R OUT OF SERVICE 1608091600-1608120100

!FDC 6/9667 MYF IAP MONTGOMERY FIELD, SAN DIEGO, CA.
ILS OR LOC RWY 28R, AMDT 4A...
MISSED APPROACH: DME REQUIRED EXCEPT FOR AIRCRAFT EQUIPPED WITH
SUITABLE RNAV SYSTEM WITH GPS.
RADAR REQUIRED FOR PROCEDURE ENTRY EXCEPT FOR AIRCRAFT EQUIPPED
WITH SUITABLE RNAV SYSTEM WITH GPS,
JLI VORTAC OUT OF SERVICE. 1608081617-1608161617EST

In Real Life, Should I Use My iPhone?

Maybe. It was an amazing thing to see my plane on the map flying down the approach plate. In real life, if DME suddenly went out, tower was closed, I had no radar vectors, and I was in IMC, or conditions were marginal, I would have been talking with ATC and executing a missed approach. In any other case, I would have had the phone out for situational awareness as a cross-check, but the aircraft equipment would have been final authority.

Flying the Clock

One thing I think I am going to try, assuming workload permits and I am well ahead of the plane, is to be aware of the speed and time to MAP from the FAF, and time it. Let's say I am going down the approach and DME goes out at the FAF or beyond. If I am timing that segment of the approach, then I can continue on or above MDA for the time given (e.g., 5 minutes in the case of the approach today into MYF) before executing a missed approach. The ability to do that would allow me to reasonably determine the MAP and might mean the difference between landing and having to execute a missed approach when I otherwise could have landed. I might also have my ipad or iphone out like I did today, as a sanity check for situational awareness.

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