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Old 28th Jul 2011, 15:14
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aterpster
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j.t.,

and we suffer an engine failure then we raise the acceleration altitude to MSA

We maintain that configuration until the missed approach altitude is reached where we level off and clean up to hold or enroute speeds

That gets us out of the configuration change/gradient problem. However, given that thrust for GA generally is the same as/similar to TO, do we give any concern to time limits at GA thrust ?

Also if a turn is required we must allow for 0.9%.

Good (although a tad higher than I might have expected) but how do we account for turn radius/terrain ?
All factors in why more than one OEI route is required for a complex location, as recommened in AC 90-121.

Using the Bishop RNAV RWY 12 "Z" IAP as the case study:

1. If the engine fails at MDA the OEI path should depart the missed approach path at ROCOS and proceed down the valley on a preplanned database RNAV OEI route. Clean up would be complete at 1,500 feet with acceleration to enroute climb and a left turn out of the valley perhaps many miles later when terrain on the east side of the valley could be safety overflown.

2. If the engine failure doesn't occur until PULIE and if we are adhering to the normal ops climb gradient we are long since cleaned up, at almost 11,000 and probably 250 KIAS. So, another evaluation needs to be preplanned at that point as to whether to continue to 13,000 along the missed approach path, or depart into the adjacent valley to the east passing TEVOC.

This can be so easily accomplished with today's state-of-the-art FMS flight plan options. It has indeed been tailored into some air carriers FMS/navigation systems by the likes of Naverus.

Alas, the industry in general is way, way, behind in taking full advantage of the capabilities of their FMS/navigation system.

Sensing an engine failure, the system could offer the crew the OEI RNAV flight path options, depended upon ship's position. The required vertical profile could also be displayed at that time.

Last edited by aterpster; 29th Jul 2011 at 22:59. Reason: added word "one"
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