FAO Chris Wonnacott

[IntheShade]

Ever wonder what FL390 looks like?

[Verbal]

Genius!

[Princess Leia]

Don't worry Shadey, I don't blame you for avoiding Tennessee until the last moment either.

[tds]

Don't worry Shadey, I don't blame you for avoiding Tennessee until the last moment either.

Outstanding warrant, perhaps?

[VectorForFood]

But did you fly the outbound leg from KDOV that night?

If you did... then a belated hello.

[Lomcevak]

[PurduePilot]

Why are they at a VFR altitude?

[OldSowBreath]

Is FL390 the Basement of outerspace, or perhaps Lower Parking Level 1 of outerspace?

[3WE]

Concorde photo[/img]

Why are they at a VFR altitude?

Odd's are they had great visibility and VMC.

[flyboy2548m]

Why are they at a VFR altitude?

You disappoint me, Bradley. How do you know they've leveled off and, besides, remind me what their altimeter would be set to above FL180.

[PurduePilot]

Why are they at a VFR altitude?

You disappoint me, Bradley. How do you know they've leveled off and, besides, remind me what their altimeter would be set to above FL180.

Well, if they weren't leveled off then there is only a 1 in 10 chance of that photo being taken while they were on a xx500 altitude. And I'm assuming the cabin display is fed by a repeater from one of the flight deck instruments, which would be set to 29.92. And correct me if I'm wrong, but Class A goes up to 60,000, which means they must be on an IFR flight plan. That being said, they're the only ones up there so ATC would probably give them whatever altitude they want. My comment was more meant for humor than anything else, as there actually aren't going to be any 172s to dodge up there...

[flyboy2548m]

Well, if they weren't leveled off then there is only a 1 in 10 chance of that photo being taken while they were on a xx500 altitude. And I'm assuming the cabin display is fed by a repeater from one of the flight deck instruments, which would be set to 29.92. And correct me if I'm wrong, but Class A goes up to 60,000, which means they must be on an IFR flight plan.

You don't reckon the cabin display might go something like "51,000...51,500...52,000 etc"? And yes, you are wrong, or at least not technically correct, as Class A extends to FL600, not 60,000', which I'm sure you know isn't the same.

[PurduePilot]

Well, if they weren't leveled off then there is only a 1 in 10 chance of that photo being taken while they were on a xx500 altitude. And I'm assuming the cabin display is fed by a repeater from one of the flight deck instruments, which would be set to 29.92. And correct me if I'm wrong, but Class A goes up to 60,000, which means they must be on an IFR flight plan.

You don't reckon the cabin display might go something like "51,000...51,500...52,000 etc"? And yes, you are wrong, or at least not technically correct, as Class A extends to FL600, not 60,000', which I'm sure you know isn't the same.

A quick google image search seems to indicate you are correct. I assumed it would have 100 foot precision. I guess they don't want the passengers to see when they deviate a bit. And good catch on the FL--you got me there.

[VectorForFood]

The Concorde was constantly changing flight levels as it chased pressure gradients

[Gabriel]

I don't know how it is in the US, but here VFR flight is restricted to the lower airspace. All flight in the upper airspace must be IFR. Now I don't remember what is was the boundary (mid twenties?), but certainly 51500ft (or FL 515) would be in the upper airspace and hence not VFR.

By the way, the standard transition level here is FL 040, or better said a FL that corresponds to about 4000ft AGL. So the transition level depends on the location but also, at least theoretically, can change with extreme weather conditions. The transition altitude is fixed for each location (about 3000ft AGL).

[PurduePilot]

I don't know how it is in the US, but here VFR flight is restricted to the lower airspace. All flight in the upper airspace must be IFR. Now I don't remember what is was the boundary (mid twenties?), but certainly 51500ft (or FL 515) would be in the upper airspace and hence not VFR.

By the way, the standard transition level here is FL 040, or better said a FL that corresponds to about 4000ft AGL. So the transition level depends on the location but also, at least theoretically, can change with extreme weather conditions. The transition altitude is fixed for each location (about 3000ft AGL).

You are correct: Class A airspace FL180-FL600 is IFR only. I was making an attempt at humor in my suggestion that the Concorde was at a VFR altitude. Transition is FL180.

[tds]

You are correct: Class A airspace FL180-FL600 is IFR only. I was making an attempt at humor in my suggestion that the Concorde was at a VFR altitude. Transition is FL180.

I thought the floor of Class A and the transition altitude was 18,000' AMSL. Flyboy's CRJ could be climbing through FL180 (defined as a specific, constant pressure) without having reached 18,000' AMSL in low pressure conditions, couldn't it?

Although I'm guessing no one would be referring to FL180 in those conditions, since FL180 wouldn't be assigned.

Right?

[PurduePilot]

You are correct: Class A airspace FL180-FL600 is IFR only. I was making an attempt at humor in my suggestion that the Concorde was at a VFR altitude. Transition is FL180.

I thought the floor of Class A and the transition altitude was 18,000' AMSL. Flyboy's CRJ could be climbing through FL180 (defined as a specific, constant pressure) without having reached 18,000' AMSL in low pressure conditions, couldn't it?

Although I'm guessing no one would be referring to FL180 in those conditions, since FL180 wouldn't be assigned.

Right?

Yeah I suppose you are correct, though couldn't FL180 be assigned on a standard or high pressure day? Not that I really need to worry about it at my lowly altitudes:

[tds]

Yeah I suppose you are correct, though couldn't FL180 be assigned on a standard or high pressure day? Not that I really need to worry about it at my lowly altitudes:

Very true!

[VectorForFood]

Sometimes we have slow pilots who request FL420, which I'm sure all of you aviation prodigys know doesn't exist

[PurduePilot]

Sometimes we have slow pilots who request FL420, which I'm sure all of you aviation prodigys know doesn't exist

Silly arbitrary RVSM rules...

[VectorForFood]

I will accept that answer as being in the close enough category...

[PurduePilot]

I will accept that answer as being in the close enough category...

No no no. I know you like me but I won't let you play favorites. Let's hear the full story.

[VectorForFood]

sorry Brad, I thought my reply went through but apparently it did not....

FL420 can't REALLY be blamed on RVSM airspace, since FL420 is not inside RVSM airspace (FL290-410).

The reasoning for the 2000' separation above FL410 is due to apparent equipment limitations and accuracy, which I would find questionable given todays technology.

Nevertheless it is what is.

[IntheShade]

The reasoning for the 2000' separation above FL410 is due to apparent equipment limitations and accuracy, which I would find questionable given todays technology.

.

Based upon?