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Hellenic aviator
27th Oct 2005, 08:43
Greetings,

I have an upcoming PC, where the STARS and approaches are all RNAV. As I am preparing, I noticed that on one of the approaches, the holding pattern depicted following the missed approach procedure is a RNAV waypoint, (Place/Bearing/Dist)whereby the hold is standard turn 4 mile legs.

Having said that, I have a couple of questions :

1) Since the hold is based on miles, am I not required to time the hold as a back up in the 'unlikely' event of a LNAV failure ?

2) If there is any timing to be done as a backup, when does the timing begin ?

I have searched the AIP and FAR/AIM but I cannot find any answers. Any help would be much appreciated. Thanking you in advance.

Fly safe

:ok:

westhawk
27th Oct 2005, 11:19
I am not aware of any requirement to time a hold which is defined by leg distance. It's either timed or has a defined leg distance as far as I know. In the case of LNAV equipment failure, an equipment failure report should be given and an amended clearance requested. An RNAV hold with 4 mile legs would be executed by flying the outbound leg until the indicated along track distance (ATD) reaches 4, then the inbound turn is executed. If you're lucky enough to be using one of the FMSs that have the capability to steer the airplane around the entire hold with LNAV engaged, you might even have enough time to complete some of those ubiquitous and ill-timed abnormal checklists! At my first training on the Honeywell, the most commonly heard question in the sim was: Aww, wherezit goin' now?

Hope that helps,

Westhawk

Hellenic aviator
27th Oct 2005, 19:02
Many thanks Westhawk ! I think the magic word (as you mentioned) is to state that there's an equipment failure and request an amended clearance.

In my Company, the convention is to start timing all holds as a backup due to a LNAV failure.....or in the event of the famous phrases "what's it doing now ?" or "Where's it going now?"

I appreciate your imput.

Safe skies :)