Narrative:

Flew an RNAV approach into sequ. This is the third RNAV I've flown into sequ and not one of them went as advertised. Descended toward dagma with an FAA guy in the cockpit. He kept trying to instruct us on how to run the VNAV! The way I understand VNAV; we don't need it engaged until prior to dagma. We can descend any way we want prior to that so long as we engage it prior to dagma and fly it down as the procedure states; but his distraction is not the point here. At dagma we were instructed by ATC to maintain 16000 ft; due to traffic that we had in the vicinity; coming from the south; I think. We were all set up for the RNAV (rnp) runway 35 but; obviously could not fly that; so we asked for and received clearance for the VOR runway 35 approach. With some quick flipping of pages and a quick brief we initiated the VOR approach (we were just a few mi from qit when we realized that we couldn't fly the RNAV). On the approach we received a GPWS warning and executed a missed approach in IMC. Came back around for another try at the RNAV approach; which after some briefing from the FAA on how to run the VNAV (real distraction in IMC; at night; in a terrain environment) we shot the RNAV to runway 35 successfully. Again; third RNAV I've flown to sequ and not one of them has gone well; or as promised in training. You had 2 experienced guys last night who were able to make it look relatively simple. It wasn't. I think that RNAV approachs could be great; but we are asking for trouble with the level of training given.

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Original NASA ASRS Text

Title: AN ACR PILOT BELIEVES THE SEQU RNAV 35 APCH REQUIRES MORE TRAINING THAN HIS CREW RECEIVED. THE APCH IS DEMANDING AT NIGHT IMC WITH TFC AND MOUNTAINS.

Narrative: FLEW AN RNAV APCH INTO SEQU. THIS IS THE THIRD RNAV I'VE FLOWN INTO SEQU AND NOT ONE OF THEM WENT AS ADVERTISED. DSNDED TOWARD DAGMA WITH AN FAA GUY IN THE COCKPIT. HE KEPT TRYING TO INSTRUCT US ON HOW TO RUN THE VNAV! THE WAY I UNDERSTAND VNAV; WE DON'T NEED IT ENGAGED UNTIL PRIOR TO DAGMA. WE CAN DSND ANY WAY WE WANT PRIOR TO THAT SO LONG AS WE ENGAGE IT PRIOR TO DAGMA AND FLY IT DOWN AS THE PROC STATES; BUT HIS DISTR IS NOT THE POINT HERE. AT DAGMA WE WERE INSTRUCTED BY ATC TO MAINTAIN 16000 FT; DUE TO TFC THAT WE HAD IN THE VICINITY; COMING FROM THE S; I THINK. WE WERE ALL SET UP FOR THE RNAV (RNP) RWY 35 BUT; OBVIOUSLY COULD NOT FLY THAT; SO WE ASKED FOR AND RECEIVED CLRNC FOR THE VOR RWY 35 APCH. WITH SOME QUICK FLIPPING OF PAGES AND A QUICK BRIEF WE INITIATED THE VOR APCH (WE WERE JUST A FEW MI FROM QIT WHEN WE REALIZED THAT WE COULDN'T FLY THE RNAV). ON THE APCH WE RECEIVED A GPWS WARNING AND EXECUTED A MISSED APCH IN IMC. CAME BACK AROUND FOR ANOTHER TRY AT THE RNAV APCH; WHICH AFTER SOME BRIEFING FROM THE FAA ON HOW TO RUN THE VNAV (REAL DISTR IN IMC; AT NIGHT; IN A TERRAIN ENVIRONMENT) WE SHOT THE RNAV TO RWY 35 SUCCESSFULLY. AGAIN; THIRD RNAV I'VE FLOWN TO SEQU AND NOT ONE OF THEM HAS GONE WELL; OR AS PROMISED IN TRAINING. YOU HAD 2 EXPERIENCED GUYS LAST NIGHT WHO WERE ABLE TO MAKE IT LOOK RELATIVELY SIMPLE. IT WASN'T. I THINK THAT RNAV APCHS COULD BE GREAT; BUT WE ARE ASKING FOR TROUBLE WITH THE LEVEL OF TRAINING GIVEN.

Data retrieved from NASA's ASRS site as of January 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.