VFR on top to IFR

PilotRPI

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PilotRPI
when it is time to descend back to ifr conditions or if clouds are ahead, what phrasing do you use? Just request “cancellation of vfr on top” or something other?
 
I'd ask for what I want.

Podunk Center, Navion 27k, request IFR descent to 5000

or

Podunk Center, Navion 27K, request IFR at 9000.
 
Cool. Thanks. They have a lot about the rules for flying vfr on too, but couldn’t find anything in the far/aim about the phrasing for the transition, and this seems like something I could use a bunch, especially in New England.
 
Cool. Thanks. They have a lot about the rules for flying vfr on too, but couldn’t find anything in the far/aim about the phrasing for the transition, and this seems like something I could use a bunch, especially in New England.
I'm curious about your thoughts on how. Most folks I've come across see VFR On Top as something for very few situations.

Although it potentially frees you to change altitudes so long as you maintain VFR cloud clearances, you are still subject to all the other rules of IFR flight. Your course is your clearance, the altitudes need to be above the minimum IFR altitudes, maintenance of communications, etc. If the goal is to stay above the clouds, it seem easy enough in most areas to request a hard IFR altitude which will do that.

Not all communications are specified in the AIM. "Cancel VFR on Top" would work well too. Since everything other than your altitude applies, they'd likely respond with an altitude to maintain.
 
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Lot’s of low layers near the coast, so I could go vfr on top and request changes in altitudes to stay above clouds as long as I am above minimum alts, no? I guess I see your point that I could also request a hard altitude assignment as IFR, but I think vfr on top allows a little more flexibility?

Newly minted license here so trying to learn the practical side of IFR since I have a decent handle on the regs.
 
Lot’s of low layers near the coast, so I could go vfr on top and request changes in altitudes to stay above clouds as long as I am above minimum alts, no? I guess I see your point that I could also request a hard altitude assignment as IFR, but I think vfr on top allows a little more flexibility?

Newly minted license here so trying to learn the practical side of IFR since I have a decent handle on the regs.
I understand your point. Yes, VFR on top would allow you the flexibility to change altitudes to maintain VFR cloud clearances, but there are at least two limitations which I think limit its usefulness.

First, ATC can specify altitudes for VFR on Top, as in "Maintain VFR-on-top at or above (altitude)..." or "Maintain VFR-on-top at or between (altitudes).

Second, the AIM also tells us to advise ATC of any altitude changes just in case there is traffic being routed there, so I'm not sure it buys that much of anything in terms of practical flexibility.

The related issue is traffic congestion. If it's one of those days with low ceilings, ATC tends to get busy. In a higher traffic area like southern New England, ATC might well refuse "the on top" clearance because it's just easier to have everyone where the want them.
 
Ahh good points. Thanks for the input. Will be interestig putting everything I learned into actual practice. Long time IFR’ers tell me I’ll never need about 75% of what I had to learn. I’m excited to keep with it.
 
Ahh good points. Thanks for the input. Will be interestig putting everything I learned into actual practice. Long time IFR’ers tell me I’ll never need about 75% of what I had to learn. I’m excited to keep with it.
Mostly true. But at the same time, you already see there are things you did not learn. Even beyond "practical," if you pay attention to the types of questions asked here, you'll see there are a bunch of regulatory and procedural questions which don't get covered in training.
 
Ahh good points. Thanks for the input. Will be interestig putting everything I learned into actual practice. Long time IFR’ers tell me I’ll never need about 75% of what I had to learn. I’m excited to keep with it.

I would echo what Mark said. It is useful to be in VMC on top, but remaining IFR gives you all the protection. VFR on top might be useful if you are trying to take a short cut through an area of low radar coverage, or mountain pass, but I don't see a lot of usefulness.
 
Yea..... Center, bugsmasher 1234R, IFR request? N1234R go ahead.... N1234R would like a pop up IFR to KLIT for the Rnav approach to rwy 22. I have Kilo at Little Rock..... N1234r squawk 4323, you are cleared to Little Rock national, fly heading 320, vectors for the Rnav 22. Descend and maintain six thousand.

Works pretty well in uncongested airspace. Cant comment on busy Class Bravo though. Never done it there.
 
Lot’s of low layers near the coast, so I could go vfr on top and request changes in altitudes to stay above clouds as long as I am above minimum alts, no? I guess I see your point that I could also request a hard altitude assignment as IFR, but I think vfr on top allows a little more flexibility?
The main thing to keep in mind about VFR-on-top is that IFR separation is not applied, you only get VFR advisories. Another thing on the practical side, is you're sure to forget you asked for it and go right back to busting through clouds. :oops: BTDT. It's not a tool you plan to use all the time, but a nice one to have in your tool box.
 
Yea..... Center, bugsmasher 1234R, IFR request? N1234R go ahead.... N1234R would like a pop up IFR to KLIT for the Rnav approach to rwy 22. I have Kilo at Little Rock..... N1234r squawk 4323, you are cleared to Little Rock national, fly heading 320, vectors for the Rnav 22. Descend and maintain six thousand.

Works pretty well in uncongested airspace. Cant comment on busy Class Bravo though. Never done it there.

Different than the OP’s situation. Your example is a pop up IFR or “abbreviated IFR flight plan.” You’re going from VFR to IFR. The OP is already IFR (OTP) and wanting a descent. It’s just a simple request for an IFR altitude.
 
OK, maybe I'm confused. If you're "VFR on top" (as opposed to "VFR over the top") you're still on an IFR flight plan right? So, it wouldn't be a pop-up IFR request, would it?

I'd expect center to hand me off to a terminal controller who'd give me a descent to an altitude and vector, or an approach clearance at some point. If I didn't get it where I'd expected, I'd just contact center with a position report. Is this not correct?
 
"Position report"? Why not just tell center you're ready to terminate VFR-on-top and would like to begin your descent, assuming you're in a radar environment?
 
I have always just asked for a "hard altitude."

Bob Gardner
 
OK, maybe I'm confused. If you're "VFR on top" (as opposed to "VFR over the top") you're still on an IFR flight plan right? So, it wouldn't be a pop-up IFR request, would it?
That is correct. If you are VFR On Top, you are still on an IFR flight plan so, no, it is not a "pop-up," a term used to describe a VFR flight requesting a clearance directly from ATC.

I'd expect center to hand me off to a terminal controller who'd give me a descent to an altitude and vector, or an approach clearance at some point. If I didn't get it where I'd expected, I'd just contact center with a position report. Is this not correct?
Center vs Terminal depends on where you are. Since you are on a IFR flight plan, the only position reports you would need to make are those you need to make on any other IFR flight; otherwise, you are on radar, just like any other IFR flight, and you will probably be sequenced for descent, approach, and landing like anyone else.

@dtuuri gave a perfect example. Again, exactly the same thing as you would say if you wanted to start your descent on any other IFR flight, except for the termination of the VFR On Top clearance.

I think the conceptual takeaway to understanding all this is: the only thing VFR On Top gives you is "some" altitude flexibility on the en route portion. Everything else is the same as any other IFR flight.
 
So you want the protection of IFR but the altitude flexibility of VFR on top. Why not as for a block altitude?
 
I'm curious about your thoughts on how. Most folks I've come across see VFR On Top as something for very few situations.

Although it potentially frees you to change altitudes so long as you maintain VFR cloud clearances, you are still subject to all the other rules of IFR flight. Your course is your clearance, the altitudes need to be above the minimum IFR altitudes, maintenance of communications, etc. If the goal is to stay above the clouds, it seem easy enough in most areas to request a hard IFR altitude which will do that.

Not all communications are specified in the AIM. "Cancel VFR on Top" would work well too. Since everything other than your altitude applies, they'd likely respond with an altitude to maintain.

I wouldn't use the word 'cancel' in this situation. @flyingron in post #2 was a good example of how to let them know you are ready to quit being OTP and need a new altitude assignment that allows you to go into the clouds. Also known as a 'hard altitude' which is a very common way of saying it as @bobmrg says in post #16. That's the phrase controllers use amongst themselves all the time about this.
 
So you want the protection of IFR but the altitude flexibility of VFR on top. Why not as for a block altitude?
No, IFR separation goes out the window—it's on you. Block altitudes take up so much airspace they only give it way out in the boondocks.
 
I wouldn't use the word 'cancel' in this situation. @flyingron in post #2 was a good example of how to let them know you are ready to quit being OTP and need a new altitude assignment that allows you to go into the clouds. Also known as a 'hard altitude' which is a very common way of saying it as @bobmrg says in post #16. That's the phrase controllers use amongst themselves all the time about this.
Yep. I see your point. "Cancel" sounds too close to "Cancel IFR," and that's not a misunderstanding you want to happen.
 
So you want the protection of IFR but the altitude flexibility of VFR on top. Why not as for a block altitude?

Got that inside the Memphis class Bravo once. They gave me from 4000 to 8000 one day where the clouds were filled with ice.
 
Could someone please explain "hard altitude" and when it would be useful?
 
Got that inside the Memphis class Bravo once. They gave me from 4000 to 8000 one day where the clouds were filled with ice.

I’ve never requested a block altitude (never had a reason to) but during training my CFII requested it so we could practice a lot of different items. I was a little more than halfway through training at the time but it was my first flight in solid IMC so it was a great opportunity and the block altitude simplified things for us and ATC. I’ll never forget it as it was the first and only time Ive gotten vertigo.
 
When you are VFR on Top you are flying a VFR altitude. To terminate VFR on Top, request an IFR altitude.
 
Could someone please explain "hard altitude" and when it would be useful?
Just means your assigned altitude (8,000) versus a block altitude (8-12,000) where you have leeway to move freely up and down the block. See EdFred's example for why it would be handy.

I got block altitudes all the time out west flying between Reno and Salt Lake City when I couldn't maintain altitude through the mountain waves. Easier to just ride the up and down drafts. ATC was usually pretty accommodating in that regard.

Cheers,
Brian
 
Just means your assigned altitude (8,000) versus a block altitude (8-12,000) where you have leeway to move freely up and down the block. See EdFred's example for why it would be handy.

I got block altitudes all the time out west flying between Reno and Salt Lake City when I couldn't maintain altitude through the mountain waves. Easier to just ride the up and down drafts. ATC was usually pretty accommodating in that regard.

Cheers,
Brian

I get block altitude, but had not heard "hard" altitude before, so it's basically your normal assigned altitude on an ifr clearance. Thanks.
 
Lol, was that an insult??? Ha, ha!

Don't they clear the airspace for Ciri-pilots? Pretty sure they do. They also push the clouds away on your route making this whole thread null and void. ....:yes:
 
Don't they clear the airspace for Ciri-pilots? Pretty sure they do. They also push the clouds away on your route making this whole thread null and void. ....:yes:

Shhh, it really ticks other pilots off when they find out, lol.
 
Could someone please explain "hard altitude" and when it would be useful?

It just means an IFR altitude assignment as opposed to VFR OTP. It is colloquial and doesn't appear in 'official' Phraseology.
 
Just means your assigned altitude (8,000) versus a block altitude (8-12,000) where you have leeway to move freely up and down the block. See EdFred's example for why it would be handy.

I got block altitudes all the time out west flying between Reno and Salt Lake City when I couldn't maintain altitude through the mountain waves. Easier to just ride the up and down drafts. ATC was usually pretty accommodating in that regard.

Cheers,
Brian

I suppose a single altitude assignment as opposed to a block of altitudes could be considered that. But it's normal use is when an airplane on an IFR clearance with an altitude assignment of VFR OTP needs to quit flying in VFR 'conditions' and get into, or close to, the clouds to continue with it's IFR clearance.
 
Could someone please explain "hard altitude" and when it would be useful?

A trip I used to make three times a week toting boxes was from Spokane to Boeing Field in Seattle. Spokane was almost always VFR, but i filed for VFR on Top; Center asked me to report my final altitude, which was almost always 6500 feet. As I approached the eastern foothills of the Cascades I could see that the Puget Sound Basin was full of clouds that were spilling over the crest. At that point I would request a hard altitude and be assigned an altitude between 8000 and 10000; I would climb to the assigned altitude and from that point on it was plain-vanilla IFR procedures.

Bob
 
Just to keep it simple: VFR on top is simply an altitude assignment on an IFR clearance. If you are unable to maintain VFR, request an IFR altitude.

I completely understand the meaning of "Hard" altitude. Used it many times... I guess I'm old....
 
A trip I used to make three times a week toting boxes was from Spokane to Boeing Field in Seattle. Spokane was almost always VFR, but i filed for VFR on Top; Center asked me to report my final altitude, which was almost always 6500 feet. As I approached the eastern foothills of the Cascades I could see that the Puget Sound Basin was full of clouds that were spilling over the crest. At that point I would request a hard altitude and be assigned an altitude between 8000 and 10000; I would climb to the assigned altitude and from that point on it was plain-vanilla IFR procedures.

Bob

That's the perfect example of why it was invented in the first place. There could have been weather at Spokane to, but when you get on top you request OTP. You don't really need or want IFR separation service from ATC enroute because that could cause delays enroute while they're keeping you away from other airplanes. Not that big a deal nowadays because of the amount of radar coverage there is. But what it gives you is, when you get close to your destination and need to get down into the goo to land, all you need is an IFR altitude assignment, aka, hard altitude. You don't have to be a 'pop up' which you would be if you had cancelled and then called for a clearance to get an Instrument let down to shoot an Approach and land. Much easier for you and the controllers. A bonus is you are being kept track of the entire way. If they lose contact with you enroute, the SAR process will be initiated 30 minutes after loss of contact, not 30 minutes after being overdue at destination if you had cancelled and pressed on VFR instead of VFR OTP.
 
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I'm curious about your thoughts on how. Most folks I've come across see VFR On Top as something for very few situations.
Back in the days of limited radar, and less traffic, it worked out to not be part of the non-radar separation scheme, but enable you to get into a place such a KBUR.

In later years, it was my only close call on TWA with a commuter IFR/VFR ontop, over LA, that nearly meshed my 767 with with a 121 commuter turboprop.
 
In later years, it was my only close call on TWA with a commuter IFR/VFR ontop, over LA, that nearly meshed my 767 with with a 121 commuter turboprop.
And there was the rather famous VFR-on-top collision in 1956 over the Grand Canyon.
 
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