IFR MEA Question

[VWGhiaBob]

What the right practice and terminology here...

I'm flying a victor airway at an altitude assigned by ATC. I notice at the next waypoint that the MEA increases by 2000 feet, but ATC doesn't say anything and I'm too low. Do I ask them first or just climb after the waypoint (assuming there's no MCA)?

 

[somorris]

I would check in with them. They probably are planning to assign the higher altitude, but may be busy doing other things.

 

[neilw2]

@somorris has it right. Check with them. In my head when flying IFR I can never change altitude unless told to do so by ATC or cleared for procedure like an approach or an arrival.

Congrats on your IFR by the way. Much more fun flying in the system than you would think!

 

[midlifeflyer]

They may or may not have you climb. There a always the possibility there is a minimum vectoring altitude below the published MEA.

Whether or not thats the case, bottom line, unless it's an emergency or lost com, we do nothing under IFR in controlled airspace absent a clearance or instruction.

 

[Sac Arrow]

They may or may not have you climb. There a always the possibility there is a minimum vectoring altitude below the published MEA.

Whether or not thats the case, bottom line, unless it's an emergency or lost com, we do nothing under IFR in controlled airspace absent a clearance or instruction.

I would concur with that.

 

[iamtheari]

Ask ATC. “Center, Bugsmasher 2-3-bravo, approaching Bigtown VOR level 5 thousand. Do you want us to climb to 6 thousand yet?” There is the possibility that you are in a lost comms scenario and they were trying to tell you to climb but you didn’t receive it. If you ask and hear nothing back, then you are lost comms and should proceed accordingly. The other possibilities are that you are thinking too far ahead (which is not a bad thing) or they forgot to climb you. There is no possibility in which it is a bad idea to ask. The only marginal one is that they are really busy (possibly in your sector or possibly in others, so you may or may not hear how busy they are) and were going to get to you, but it still harms nobody to ask and be certain of what’s going to happen.

 

[luvflyin]

yeah on all of the above. If your flyin a dog that don't climb very good I might ask about a minute before I get there

 

[Kritchlow]

I remember way back, before GPS, I flew a C310 from DTW to ???
Anyway, I was crossing Lake Michigan and the MEA was above my assigned cruise. I’m thinking 3000 vs 10000. Sure the MOCA was low, but when I told ATC I needed to climb to MEA they truly had a fit. They had no clue. The route was somewhere between DTW and BUF.

 

[Kritchlow]

Damn I’m digging into history for that one.

 

[Rykymus]

The way I was taught to view it was that you are on an IFR flight plan so that "if" you lose comms, you can continue your flight according to your clearance and the charts. As long as you are in communication with ATC, it's "mother may I". "When you lose comms, that's when the MEA comes into play.

 

[luvflyin]

I remember way back, before GPS, I flew a C310 from DTW to ???
Anyway, I was crossing Lake Michigan and the MEA was above my assigned cruise. I’m thinking 3000 vs 10000. Sure the MOCA was low, but when I told ATC I needed to climb to MEA they truly had a fit. They had no clue. The route was somewhere between DTW and BUF.

Looks like Eirie, not Michigan. There are big differences between MEA and MOCA through there. So what was the verdict? Did they give give you MEA after they calmed down?

 

[Kritchlow]

Looks like Eirie, not Michigan. There are big differences between MEA and MOCA through there. So what was the verdict? Did they give give you MEA after they calmed down?

Yeah... likely Erie. I remnembef actually arguing with the controller. Can’t remember the outcome. I knew I wouldn’t hit anything so I wasn’t overly worried.
I do remember I had a wad of fuel injectors in the back of the plane. The boxes wouldn’t fit so we took them out. They were a tangled mess.

 

[Tantalum]

Aren't MEAs designed for VOR nav? Many of the blue GPS altitudes are much lower. If I'm flying via GPS /g and I'm above the MOCA I wouldn't bother them

 

[midlifeflyer]

Aren't MEAs designed for VOR nav? Many of the blue GPS altitudes are much lower. If I'm flying via GPS /g and I'm above the MOCA I wouldn't bother them

Yes, you would look at the other depicted minimum IFR altitudes.

@VWGhiaBob did mention that the climb doesn't have to start until the the change over point unless there's an MCA. If he knows that (and a lot of folks don't) I'm guessing he knows about MOCA and GPS altitudes and is asking about a "pure" MEA situation.

 

[PaulS]

"What's my vector victor?"

 

[Larry in TN]

91.173 ATC clearance and flight plan required.

91.177 Minimum altitudes for IFR operations.

"[facility], [callsign], request [altitude]"

 

[FlyingTiger]

Ask ATC. “Center, Bugsmasher 2-3-bravo, approaching Bigtown VOR level 5 thousand. Do you want us to climb to 6 thousand yet?” There is the possibility that you are in a lost comms scenario and they were trying to tell you to climb but you didn’t receive it. If you ask and hear nothing back, then you are lost comms and should proceed accordingly. The other possibilities are that you are thinking too far ahead (which is not a bad thing) or they forgot to climb you. There is no possibility in which it is a bad idea to ask. The only marginal one is that they are really busy (possibly in your sector or possibly in others, so you may or may not hear how busy they are) and were going to get to you, but it still harms nobody to ask and be certain of what’s going to happen.

"If I wanted you to climb I would of said so. Did you ever hear of minimum vectoring altitudes HOBBY PILOT! GTF off my frequency!" ......5 seconds later, "Bugmasher 2-3-bravo, Climb and maintain 6,000"

 

[frfly172]

Do nothing before or untill talking to the controller. Of course haven’t flow an airway for quite a while. Gotta love direct to.

 

[jaybee]

anytime there is any kind of question about anything ask. ask. ask. ask. ask. i don't give one flip if they get annoyed or have to repeat something 22 times. i'm the one dying not them.

can't tell you how many times i've been handed off in a bugsmasher and given "direct to" - aaaaaahhhhhh "im slash alpha...." "ummmm... hold on..." a minute goes by, "fly heading xxx"

in a lot of cases they are understaffed, overworked and possibly accustomed to working the airliners, a bugsmasher can be hard for their brain to compute sometimes, not cause they are dumb or anything just because they spend most of their day working airliners

 

[flyingron]

yeah on all of the above. If your flyin a dog that don't climb very good I might ask about a minute before I get there

Unless there's an MCA you have to be in a real dog that it would make a difference.

 

[luvflyin]

Yes, you would look at the other depicted minimum IFR altitudes.

@VWGhiaBob did mention that the climb doesn't have to start until the the change over point unless there's an MCA. If he knows that (and a lot of folks don't) I'm guessing he knows about MOCA and GPS altitudes and is asking about a "pure" MEA situation.

Hmm. He flies a Cirrus I think so I'm guessing he was using GPS. The rule that MOCA is 'officially' authorized for GPS aircraft is pretty new, just a few months ago. Was there a MOCA @VWGhiaBob

EDIT: By "MOCA is 'officially' authorized for GPS aircraft......" I mean that it is new that controllers can 'assign' it. See post #'s 27, 29 and 31

 

[luvflyin]

Unless there's an MCA you have to be in a real dog that it would make a difference.

Yeah. @aterpster, do you know offhand what the assumed climb angle is when they plot this stuff out? EDIT: @flyingron already answered it. EDIT,EDIT: @Tantalum knew it to.

 

[flyingron]

It's dependent on altitude.

Sea level through 5,000 feet MSL—150 feet per NM,
5000 feet through 10,000 feet MSL—120 feet per NM,
10,000 feet MSL and over—100 feet per NM

The angle is arctan( feet per nautical mile / 6076).

 

[Tantalum]

My instrument instructor was bing on this stuff, it is in the TERPS:
sea level to 5K MSL is 150fpnm
5K to 10K MSL is 120fpnm
Above 10K is 100fpnm

So Archer at 120 GS at 7K MSL will need 240 ft/m

EDIT: @flyingron beat me to it

 

[luvflyin]

My instrument instructor was bing on this stuff, it is in the TERPS:
sea level to 5K MSL is 150fpnm
5K to 10K MSL is 120fpnm
Above 10K is 100fpnm

So Archer at 120 GS at 7K MSL will need 240 ft/m

EDIT: @flyingron beat me to it

Who was your instructor? PM me if you don't want to through his name out here.

 

[Tantalum]

@luvflyin I don't mind giving him a plug, Dave Simpson at http://www.takeflightsandiego.com/

 

[midlifeflyer]

Hmm. He flies a Cirrus I think so I'm guessing he was using GPS. The rule that MOCA is 'officially' authorized for GPS aircraft is pretty new, just a few months ago. Was there a MOCA @VWGhiaBob

Do you have a cite for the "official" authorization you are referring to. I always though 91.177(a), which was amended in 2007 in order to cover this situation, was official enough.

However, if both a MEA and a MOCA are prescribed for a particular route or route segment, a person may operate an aircraft below the MEA down to, but not below, the MOCA, provided the applicable navigation signals are available. For aircraft using VOR for navigation, this applies only when the aircraft is within 22 nautical miles of that VOR (based on the reasonable estimate by the pilot operating the aircraft of that distance)​

 

[denverpilot]

Unless there's an MCA you have to be in a real dog that it would make a difference.

Must be a lot of “dogs” around here.

 

[luvflyin]

Do you have a cite for the "official" authorization you are referring to. I always though 91.177(a), which was amended in 2007 in order to cover this situation, was official enough.

However, if both a MEA and a MOCA are prescribed for a particular route or route segment, a person may operate an aircraft below the MEA down to, but not below, the MOCA, provided the applicable navigation signals are available. For aircraft using VOR for navigation, this applies only when the aircraft is within 22 nautical miles of that VOR (based on the reasonable estimate by the pilot operating the aircraft of that distance)​

Yeah. I was making reference to it becoming 'official' to controllers that they could 'assign' the MOCA to GPS aircraft beyond 22nm from the Navaid. I think it was back around October. It was like someone finally got around to acknowledging that GPS was an 'applicable navigation signal.' I'll try to find it for you.

 

[Palmpilot]

Do I remember rightly that communications capability is not guaranteed at the MOCA?

 

[luvflyin]

Do you have a cite for the "official" authorization you are referring to. I always though 91.177(a), which was amended in 2007 in order to cover this situation, was official enough.

However, if both a MEA and a MOCA are prescribed for a particular route or route segment, a person may operate an aircraft below the MEA down to, but not below, the MOCA, provided the applicable navigation signals are available. For aircraft using VOR for navigation, this applies only when the aircraft is within 22 nautical miles of that VOR (based on the reasonable estimate by the pilot operating the aircraft of that distance)​

https://www.faa.gov/documentLibrary...s_to_GNSS_Equipped_Aircraft_Below_the_MEA.pdf

 

[flyingron]

Must be a lot of “dogs” around here.

Not sure what point you're trying to make. Those are MRAs in that chart snippet. MRA's are set because of the inability to receive the crossing radial signal at a lower altitude. They have nothing to do with terrain or on-airway course guidance.

 

[denverpilot]

Not sure what point you're trying to make. Those are MRAs in that chart snippet. MRA's are set because of the inability to receive the crossing radial signal at a lower altitude. They have nothing to do with terrain or on-airway course guidance.

I was generally chuckling at the idea that minimum IFR altitudes if any sort “don’t make much difference” and it’s all the airplane’s fault for being a “dog”. All sorts of MEAs around here that a typical GA aircraft would struggle to get to.

 

[midlifeflyer]

Do I remember rightly that communications capability is not guaranteed at the MOCA?

I don't know if "guaranteed" is part of the definition but since both VOR and com are line of sight means ATC might not assign a MOCA if they can't.

There are areas where you lose com at the MEA.

 

[midlifeflyer]

https://www.faa.gov/documentLibrary...s_to_GNSS_Equipped_Aircraft_Below_the_MEA.pdf

Thank you.

 

[luvflyin]

I don't know if "guaranteed" is part of the definition but since both VOR and com are line of sight means ATC might not assign a MOCA if they can't.

There are areas where you lose com at the MEA.

Supposedly, communication is a requirement for the establishment of an airway. Maybe its just to the MEA, I'm not really sure and I think there have been some changes to things over the last few years that have allowed 'Data Link' to satisify the requirement, so 'radio communication' may not be necessary. Anyway, issuing Lost Com is a requirement for controllers when clearing aircraft below the MEA. Sometimes. Here's the 'rules.'

a. An aircraft may be cleared below the MEA but not below the MOCA for the route segment being flown if the altitude assigned is at least 300 feet above the floor of controlled airspace and one of the following conditions are met:
NOTE− Controllers must be aware that in the event of radio communications or GNSS failure, a pilot will climb to the MEA for the route segment being flown.
1. For aircraft using VOR, VORTAC or TACAN for navigation, this applies only within 22 miles of that NAVAID.
2. When radar procedures are used, the following actions are taken:
(a) In the absence of a published MOCA, assign altitudes at or above the MVA or MIA along the route of flight, and
(b) Lost communications instructions are issued.
3. The aircraft is GNSS equipped.

"2. (b)" kind of implies that radio communication is not protected for below the MEA. "3." was recently added.

 

[flyingron]

I was generally chuckling at the idea that minimum IFR altitudes if any sort “don’t make much difference” and it’s all the airplane’s fault for being a “dog”. All sorts of MEAs around here that a typical GA aircraft would struggle to get to.

I didn't say that altitudes don't matter. I said that unless there is a crossing restriction, the airway design always accounts for a rather conservative climb AT the MRA change point. 150FPMile in a 120knot plane is only 300 FPMinute climb. As already mentioned, the rate of climb expected is shallower as altitude goes up.

My comment on dogs was countering the suggestion that you would need to ask for a climb prior to hitting the MEA change point.

 

[denverpilot]

I didn't say that altitudes don't matter. I said that unless there is a crossing restriction, the airway design always accounts for a rather conservative climb AT the MRA change point. 150FPMile in a 120knot plane is only 300 FPMinute climb. As already mentioned, the rate of climb expected is shallower as altitude goes up.

My comment on dogs was countering the suggestion that you would need to ask for a climb prior to hitting the MEA change point.

Ah okay, fair enough. We have boatloads of SIDs that are non-standard feet/nm ‘round here also.

 

[midlifeflyer]

Supposedly, communication is a requirement for the establishment of an airway.

Supposedly it is. But there are gaps here and there. There is (or was) one on V611 between the Colorado/New Mexico Border and KLVS. I learned that one when Alburquerque Center advised me we would lose com for about 10 miles.

 

[denverpilot]

Supposedly it is. But there are gaps here and there. There is (or was) one on V611 between the Colorado/New Mexico Border and KLVS. I learned that one when Alburquerque Center advised me we would lose com for about 10 miles.

BTDT. Same airway. LOL.