MEA vs MOCA?

[apcooper]

As you all know on IFR enroute charts you see an MEA and sometimes an MOCA on each airway. Since the MEA guarentees adaquate terrain clearance as well as nav signal coverage if flying /G can you fly at the MOCA even when farther than 22NM from the navaids since obviously GPS is independent from any ground based navaids. It is really a pain that on some airways the MEA can be several thousand feet above the MOCA.

 

[User546]

Are we assuming that your flying GPS routing, as opposed to VOR routing. Direct To vs. Airways?

If your usign a GPS to navigate, wouldn't this be a mute point? Or do you program airways into you GPS and fly them that way?

 

[satpak77]

always fly at or above the published MEA's, period

 

[minitour]

always fly at or above the published MEA's, period

As a safety precaution, yes I agree.

With the MOCA though...all I can think of is that they can be used if you're using GPS to navigate on the airway.

If you're off-airway then you've got the OROCA to play with.

-mini

 

[User546]

With the MOCA though...all I can think of is that they can be
used if you're using GPS to navigate on the airway.

Which may work great, until you lose your GPS integrity signal, and now you find yourself on an airway, underneath the MEA, chacnes are more then 22NM from a VOR, and no form of navigation! DOHH!!!

 

[minitour]

Which may work great, until you lose your GPS integrity signal, and now you find yourself on an airway, underneath the MEA, chacnes are more then 22NM from a VOR, and no form of navigation! DOHH!!!

yup

sux even more if you dont have the performance to get back to MEA..

...that was an instrument oral question...

-mini

 

[satpak77]

repeating

always fly at or above the published MEA's, period

repeat after me....

ALSO:

If you are off-airway, in non-radar environment (South America, etc), via GPS, and you have to put down somewhere, where is SAR gonna look for you?

Stay on the airway, and that gives them a start.

 

[Immelman]

Doesnt radar coverage also factor into MEA vs. MOCA? I remember some airways here out west with FL180 MEAs that I *thought* were that high because of radar coverage issues (highest terrain along the route maybe 8-10k).

 

[satpak77]

Doesnt radar coverage also factor into MEA vs. MOCA? I remember some airways here out west with FL180 MEAs that I *thought* were that high because of radar coverage issues (highest terrain along the route maybe 8-10k).

MVA is the only "altitude" (for our discussion) that is radar dependent. It is Minimum Vectoring Altitude. It has always been my interpretating that MEA (Note, it means MINIMUM) altitude is "worst case" scenario, lost-comm, no radar, etc.

If you are AT MEA, and you get an engine failure, problems, etc, now you are immediately below MEA, playing catch-up.

Always be ABOVE MEA when possible, and AT the MEA at all other times.

 

[apcooper]

Doesnt radar coverage also factor into MEA vs. MOCA?

As far as I know radar coverage has nothing to do with it. In Arctic Canada you have relativly low MEA's and most likely have no radar coverage. All non-radar means is that you have to give position reports, fly full approaches, no traffic callouts, no vectors, no low altitude alert, and lots of holding!! Terrain has nothing to do with it. If you are unlucky enough to fly in the NE corridor and the antenna is blown down in a windstorm the all this would happen going into TEB. What fun, huh!![/QUOTE]