VFR on top

ErikU

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ErikU
This has probably been answered, but this system will not let me search for it...

I have never used VFR on top, but from what I understand I can request and be issued a clearance for it so long as I maintain VFR at VFR altitudes.

My question is this...

Over mountainous terrain, can I climb to VFR on top at an altitude that is less that the "minimum vectoring altitude"? Since I will be in VFR conditions, and can maintain my own terrain clearance, why not? Of course, I will probably want an altitude that will allow ATC to pick me up on radar, but I don't want to deal with terrain altitudes if I can see the terrain.

Anyone know?
 
From the AIM Section 5-5-13a, which covers pilot responsibilities for VFR-on-top operations:
(c) Comply with instrument flight rules that are applicable to this flight; i.e., minimum IFR altitudes, position reporting, radio communications, course to be flown, adherence to ATC clearance, etc.
Thus, you'll have to fly at least at the MEA on airways and the MVA (or other computed MIA that provides both terrain clearance and navaid reception) off airways.
 
Your better bet would be two IFR flight plans. One to a point where you're on top, and then close it cancel it. Fly VFR at the altitudes less than MEA/MOCA if you can, and then get your second IFR clearnace from some fix somewhere to your ultimate destination if need be.
 
Despite being clearly against the regs, I believe that this is often done. I've had it "offered to me" before (in Colorado), and I've heard other pilots who've done the same.
-harry
 
Despite being clearly against the regs, I believe that this is often done. I've had it "offered to me" before (in Colorado), and I've heard other pilots who've done the same.
-harry
The regs Ron posted were for VFR on top. Out here ATC will frequently ask if you can maintain your own terrain separation in the climb, or you can request it, but that doesn't count as VFR on top.
 
Thanks for the tips..

I'll try it with on top. If it doesn't work I'll just cancel once I'm on top and air file for the second leg at the destination.
 
The regs Ron posted were for VFR on top. Out here ATC will frequently ask if you can maintain your own terrain separation in the climb, or you can request it, but that doesn't count as VFR on top.
I've been offered by Denver Center to remain on my IFR clearance if I would maintain my own terrain separation in circumstances where it clearly was not for the purpose of the climb (I was somewhere around RIL on V8 enroute from KCNY to KAPA). On the same flight, I also heard ATC offer own terrain separation on an IFR descent.

As harry said, nothing in the rules permits it, but it's done (btw, I declined the offer in my case, canceled IFR and continued VFR with flight following).
 
I used to fly boxes between BFI and OAK at night and between BFI and GEG in the daytime....I guess you could call that flying over the mountains. I routinely filed for VFR-on-top out of Spokane even when the sky was clear, because I knew that when I got to the middle of the Cascades and saw the clouds peeping over the ski areas, all I had to do was ask for a "hard altitude" and I would be back in the for-real IFR system ready for an approach into BFI. It is a great tool, and I advise you to use it whenever you can.

I did have to observe the MEAS, though, and because too much altitude is better than too little, that was fine with me.


Bob Gardner
 
The regs Ron posted were for VFR on top. Out here ATC will frequently ask if you can maintain your own terrain separation in the climb, or you can request it, but that doesn't count as VFR on top.

We get that a lot our here, too. When Portland Approach closes at midnight, they hand the airspace between RKD and AUG over to BOS Center. Portland's radar gets us down to about 1800 feet, but Boston can't go much below 6,000. Since we usually fly that leg at 3,000, they let us stay low so long as we "assume responsibility for our own terrain and obstacle clearance." We still have to follow all the normal IFR rules and climb if the vis drops, but it's nice to not have to fly a parabola for that leg.
 
Surprisingly, I was able to do this today!

I was on an airway with a MEA of 10,000ft. I wanted off the airway for t-storms that I could see. Asked to deviate 20 degrees right, but was told no because that would put me too close to Mt Rainier and I would be well below the MVA (and I didn't want to climb to go over). I asked if I could do it VFR on top and they said yes, "altitude and heading at your discretion, maintain VFR on top".

So, for me, this worked and was great!
 
Your better bet would be two IFR flight plans. One to a point where you're on top, and then close it cancel it. Fly VFR at the altitudes less than MEA/MOCA if you can, and then get your second IFR clearnace from some fix somewhere to your ultimate destination if need be.
This is an excellent question. In reality, VFR on Top comes up so infrequently, that controllers may differ in their opinion of the answer.
If you are VFR on top, but still on an IFR flight plan, are you still being separated by applicable IFR minimums?
I believe that the answer is yes, but some would say no.
Therefore, I agree with EdFred's answer. You are better off with another IFR flight plan waiting for you in the event that the controller removes your initial IFR flight plan from the system.:blueplane:
ApacheBob
 
We get that a lot our here, too. When Portland Approach closes at midnight, they hand the airspace between RKD and AUG over to BOS Center. Portland's radar gets us down to about 1800 feet, but Boston can't go much below 6,000. Since we usually fly that leg at 3,000, they let us stay low so long as we "assume responsibility for our own terrain and obstacle clearance." We still have to follow all the normal IFR rules and climb if the vis drops, but it's nice to not have to fly a parabola for that leg.
Because Illinois is flat, that does not come up here too often.
But I would have expected that a "cruise" clearance would be used in that case, not VFR on top.
They work in that environment, so they would know better than me.
ApacheBob
 
Because Illinois is flat, that does not come up here too often.
But I would have expected that a "cruise" clearance would be used in that case, not VFR on top.
They work in that environment, so they would know better than me.
ApacheBob
Yeah, I was thinking Cruise Clearance, but when I went to the AIM I couldn't find the entry quickly, so didn't reply.
 
Surprisingly, I was able to do this today!

I was on an airway with a MEA of 10,000ft. I wanted off the airway for t-storms that I could see. Asked to deviate 20 degrees right, but was told no because that would put me too close to Mt Rainier and I would be well below the MVA (and I didn't want to climb to go over). I asked if I could do it VFR on top and they said yes, "altitude and heading at your discretion, maintain VFR on top".

So, for me, this worked and was great!
Bear in mind though, that, depending on whether you accept the AIM recommendation as the rule (the old "AIM is not regulatory" issue)you did not in fact "maintain VFR on top," since the AIM clearly tells you you need to abide MEAs.

Assuming the AIM reflects the real rule (it arguably does - since you are still in fact on an IFR clearance. 91.177 should still apply), what you did was roughly the regulatory equivalent of being a VFR pilot flying through a cloud while being vectored in Class B airspace.

Just food for thought. Practical application? Heck, if ATC lets you go below the MEA at your discretion when VFR On-Top when you maintain your own terrain separation, it is in fact severe clear with no chance of running into a cloud, and you are able to maintain your IFR routing, who's likely to report it for enforcement action?
 
If you are VFR on top, but still on an IFR flight plan, are you still being separated by applicable IFR minimums?
I believe that the answer is yes, but some would say no.
I think you can add the FAA to the "some would say no" column:

==============================
Although standard IFR separation is not applied, controllers shall continue to provide traffic advisories and safety alerts, and apply merging target procedures to aircraft operating VFR-on-top.
==============================
ATC Handbook, 7-3-1, Note 2.

(BTW, FWIW, there is nothing in the ATC Handbook about handing terrain separation responsibilities over to the pilot, except in the sections about pop-up IFR clearance requests by VFR flights)
 
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Because Illinois is flat, that does not come up here too often.
But I would have expected that a "cruise" clearance would be used in that case, not VFR on top.
They work in that environment, so they would know better than me.
ApacheBob

No, you're absolutely right, Bob, it was a cruise clearance, though they didn't call it that. We weren't on top (we were 4,000 feet below the lowest ceiling), they just left the responsibility for terrain and obstacle clearance to us so we didn't have to climb into their radar coverage. I was mostly just providing an anecdote in support of what Mari and Mark said, not so much about the VFR on top.
 
It sure turned out to be a great tool for me on a very challenging IFR flight.

Challenging in a different way than usual. It wasn't really technically challenging, but there was constant evaluation of options and making decisions.

I was trying to cross a mountain pass, at and angle. I could see through to the other side (overcast layer above), I could have gone VFR and been 2500ft above terrain and legal VFR. However, there were buildups all over and I wouldn't have any way of knowing if I flew under one. I decided not to chance serious down drafts while only 2500ft over the mountains.

Basic IFR wasn't an option because I didn't want to fly in to embedded buildups.

Getting on top in the area of suspected weather and weaving my way around the buildups was the safest option, the trick was being allowed off the airway below MVA. A great solution.
 
It sure turned out to be a great tool for me on a very challenging IFR flight.
The regulatory MEA issue aside, were you able to keep VFR cloud separation (remembering that if you were above 10,000 msl, it's 1,000' above, 1,000' below and 1 mile away)? (Unless course you were close enough to the ridges or in airspace where your altitude meant that you were in Class G)
 
This is an excellent question. In reality, VFR on Top comes up so infrequently, that controllers may differ in their opinion of the answer.
If you are VFR on top, but still on an IFR flight plan, are you still being separated by applicable IFR minimums?
I believe that the answer is yes, but some would say no.
Therefore, I agree with EdFred's answer. You are better off with another IFR flight plan waiting for you in the event that the controller removes your initial IFR flight plan from the system.:blueplane:
ApacheBob

I can't find the EdFred post you refer to, but there is no way a controller could remove your intial IFR flight plan from the system because going VOTP does not take you out of the IFR system...it is an IFR clearance.

Bob Gardner
 
This is an excellent question. In reality, VFR on Top comes up so infrequently, that controllers may differ in their opinion of the answer.
If you are VFR on top, but still on an IFR flight plan, are you still being separated by applicable IFR minimums?
I believe that the answer is yes, but some would say no.
Therefore, I agree with EdFred's answer. You are better off with another IFR flight plan waiting for you in the event that the controller removes your initial IFR flight plan from the system.:blueplane:
ApacheBob

The controller can't "remove your initial IFR flight plan from the system" any more with VOTP than with any other kind of IFR operation....VOTP is an IFR clearance from beginning to end. A controller cannot unilaterally terminate your IFR without your concurrence. :no:


Bob Gardner
 
This is an excellent question. In reality, VFR on Top comes up so infrequently, that controllers may differ in their opinion of the answer.
If you are VFR on top, but still on an IFR flight plan, are you still being separated by applicable IFR minimums?
I believe that the answer is yes, but some would say no.

OTP is an IFR clearance but due to the VFR part you are responsible for maintaining separation and VMC (and that includes being 1000 ft above the clouds etc). According to the "controller's bible (Order 7110), ATC is required to prevent "merging targets" but that's it. ATC may at their discretion (workload permitting etc) provide advisories but don't count on it. In looking this up I also learned a couple other things about OTP. One is that it's only available from sunrise to sunset and the other is that it's legal to fly an off airway route that exceeds the SSVs of the navaids used.

Therefore, I agree with EdFred's answer. You are better off with another IFR flight plan waiting for you in the event that the controller removes your initial IFR flight plan from the system.:blueplane:
ApacheBob

This is definitely not the way I'd go. There's no guarantee that ATC will give you a clearance at the destination. Having a flight plan on file without a clearance only implies that you shouldn't have to supply all the data required.

ATC should never cancel your IFR clearance unless you request it or have landed at a towered field. That doesn't mean this can't happen, just that it shouldn't. When cleared OTP you are still required to follow the assigned course and must stay in communication with ATC as you would on any other IFR clearance.
 
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