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wilco77
27th Nov 2018, 04:37
Hi can anyone share with me the regulatoons for block altitude clearances between FAA and Air Services Australia.

What are the threats associated with it and if anyone has any material on block altitudes.

thanks

wilco

MarkerInbound
27th Nov 2018, 15:49
There are no CFR 14 regulations regarding block altitudes in the FAA system. If you flew outside of your cleared altitudes you could be subject to a violation like any clearance. The Instrument Pilot Handbook and the Air Traffic Control order simply say it is a block of altitudes assigned by ATC to allow altitude deviations. The IPH also suggests requesting a block if you are unable to maintain altitude due to turbulence.

sleeve of wizard
27th Nov 2018, 16:15
The Australian AIP has the following guidance,

6.8 Block Level Clearances

6.8.1 Subject to traffic, ATC may issue block level clearances to facilitate operations in adverse weather or to allow flight crews to optimise fuel burn for an aircraft.
6.8.2 A block level clearance is cancelled or amended by the issuing of a new vertical clearance.
6.8.3 To request a cancellation of a block clearance when it is no longer required, flight crews should downlink a CPDLC request for the preferred level in order to enable ATC to issue the new vertical clearance.

A Squared
27th Nov 2018, 16:18
Hi can anyone share with me the regulatoons for block altitude clearances between FAA and Air Services Australia.

What are the threats associated with it and if anyone has any material on block altitudes.

thanks

wilco


There really aren't any "regulations" as such. About the only regulations applicable are the general regulations which require you to comply with ATC clearances.

What are the threats associated with it ...

You're trying to get PPrune to do your class assignment, aren't you?

wilco77
28th Nov 2018, 02:29
Thanks for the replies and info everyone.

Cheers
Wilco

LeadSled
28th Nov 2018, 04:10
There are no CFR 14 regulations regarding block altitudes in the FAA system. If you flew outside of your cleared altitudes you could be subject to a violation like any clearance. The Instrument Pilot Handbook and the Air Traffic Control order simply say it is a block of altitudes assigned by ATC to allow altitude deviations. The IPH also suggests requesting a block if you are unable to maintain altitude due to turbulence.

Markerinbound ( and wilco77)
Not quite so, refer to a "Cruise" clearance, this is a block altitude clearance of a particularly flexible king, see the FAA AIM and the Pilot/Controller Glossary.
Tootle pip!!

MarkerInbound
28th Nov 2018, 15:05
There are also no regulations about cruise clearances. A cruise clearance is different from a block altitude clearance in that it includes an approach clearance and once you report descending out of an altitude you can't go back up to that altitude. Those differences are pointed out in the AIM which says in its preface that it is not regulatory. So if a pilot failed to comply with the conditions of a cruise clearance they would be violating 91.123 and not some cruise clearance regulation. In 40+ years of IFR flying I've only received a cruise clearance one time between Maui and Kona in the middle of the night.

donpizmeov
28th Nov 2018, 16:09
Block Altitude clearances are often given in both New Zealand and Australian FIRs . Before RVSM they were a great way of stating close to optimum ALT . With RVSM if the airspace is empty enough to allow a block clearance, it empty enough to allow you to cruise within 1000 feet of optimum, which is probably good enough .

A Squared
28th Nov 2018, 16:42
In 40+ years of IFR flying I've only received a cruise clearance one time between Maui and Kona in the middle of the night.

Not a cruise clearance, exactly, but a former employer had a nightly mail run from Anchorage to Fairbanks. IIRC, we'd typically arrive in Fairbanks about 10 pm or so. More than once We'd check in with Fairbanks approach and get: "Cleared Visual Approach Rwy 1L, Cleared to Land, Cleared to taxi to parking". Saved a lot of wear and tear on the radios.

hans brinker
28th Nov 2018, 16:48
Not a cruise clearance, exactly, but a former employer had a nightly mail run from Anchorage to Fairbanks. IIRC, we'd typically arrive in Fairbanks about 10 pm or so. More than once We'd check in with Fairbanks approach and get: "Cleared Visual Approach Rwy 1L, Cleared to Land, Cleared to taxi to parking". Saved a lot of wear and tear on the radios.

Used to do the Palma de Mallorca to Ibiza shuttle on the DHC8, 20 minute legs. After T/O from rwy 24R in PMI, contact departure, "ANS8252, radar contact, climb FL80, turn left 10 degrees, intercept the localizer, cleared ILS approach rwy 24 IBZ". Next call was to contact the tower over the marker.

GlenQuagmire
28th Nov 2018, 16:58
I have had block clearances across the US a couple of times - asked for and was given a block FL430-FL490 - and its great. I love flying in America. Your beer is crap but your sky is big..

misd-agin
29th Nov 2018, 01:42
I have had block clearances across the US a couple of times - asked for and was given a block FL430-FL490 - and its great. I love flying in America. Your beer is crap but your sky is big..

1,400 breweries in England vs. 6,300 in the U.S. If you didn't find a beer to your liking you should have keep looking.

Block altitudes are a good option. They can also help when you're trying to find the best ride through an area of turbulence.

Pontius
29th Nov 2018, 02:31
1,400 breweries in England vs. 6,300 in the U.S. If you didn't find a beer to your liking you should have keep looking.

By my maths that makes 1 brewery every 93 km2 in England versus 1 brewery every 1561 km2 in the USA.......that's a LOT of looking. There is the perpetual problem of finding decent beer in the US and it's not helped by the lack of breweries per km2 :}:}:}

LeadSled
29th Nov 2018, 08:13
There are also no regulations about cruise clearances. A cruise clearance is different from a block altitude clearance in that it includes an approach clearance and once you report descending out of an altitude you can't go back up to that altitude. Those differences are pointed out in the AIM which says in its preface that it is not regulatory. So if a pilot failed to comply with the conditions of a cruise clearance they would be violating 91.123 and not some cruise clearance regulation. In 40+ years of IFR flying I've only received a cruise clearance one time between Maui and Kona in the middle of the night.

Marker,
Although it may surprise you, I do/did know that, and you are playing with semantics. It come with too may hours, over too many years, flying in US ( and lots of other) airspace.
There probably isn't an FAR that says many brown Burmese cats you can carry on a N- freighter, but that doesn't mean you can't carry brown Burmese cats on said freighter.
I seriously suggest you look a little more widely, rather than expecting a specific regulation to allow or prohibit whatever it is you want to do.
ATC, FAA style, is commendably practical and flexible.
The "law" around violating a clearance is also reasonably straightforward, which seems to be your hangup.
Tootle pip!!

PS: Re. the AIM, I would give careful and more in-depth study to the caveats and limitations, if I were you.

Airmann
29th Nov 2018, 08:53
Just remember that once issued a block altitude all calls to ATC must state the block that you are maintaing, with no reference to your current altitude.

I read recently about the potential of both block altitude and cruise climb availability over the Atlantic. However, given the level of traffic I haven't even dared to ask. Has anyone here done so?

And with regard to cruise climb, I understand that the basic difference between it and a block altitude is that in the former once you climb you can never descend, but are there any other differences?

MarkerInbound
29th Nov 2018, 15:41
Leadsled, This is pprune, the center of the pedantic universe. I could have told the OP the regulation regarding block altitude clearances is the same as for a fixed altitude. You have to abide by it. A block altitude clearance is normally at the request of the flight crew due to weather or maneuvering. A cruise clearance is issued by ATC in lieu of a fixed altitude. I look at them as two totally different things.

Ian W
29th Nov 2018, 17:41
Just remember that once issued a block altitude all calls to ATC must state the block that you are maintaing, with no reference to your current altitude.

I read recently about the potential of both block altitude and cruise climb availability over the Atlantic. However, given the level of traffic I haven't even dared to ask. Has anyone here done so?

And with regard to cruise climb, I understand that the basic difference between it and a block altitude is that in the former once you climb you can never descend, but are there any other differences?

Cruise climb causes considerable consternation with some air traffic service providers and the ICAO Global Operational Data Link document (GOLD) repeatedly warns:
Note.— Avoid use of this message element due to potential misinterpretation

The idea with a cruise climb is to set engines to the most efficient power setting then instead of maintaining level just allow the aircraft to climb as weight reduces. The issues are that if the outside air temperature warms then (due to the thermodynamics of the engines) the aircraft will lose power and descend. Hence the warning that the aircraft should not be allowed to descend, but to stop that means adjusting engine power so defeats some of the object. This is the reason for allocation of a Block [bottom] to [top] as the aircraft is only required to stay in the block and can be separated from other aircraft. Of course it also means that you have just been allocated a huge chunk of airspace. As normally the block starts at one waypoint and extends to another.

As ATM tools improve they are becoming more capable of deconflicting aircraft on cruise climb and some authorities namely NAV Canada are more approachable on cruise climb than others some will not even countenance the idea. So that is why aircraft are given step climbs that approximate to a cruise climb but in a series of level segments. Not ideal as the engines are required to accelerate to climb power for the climb between level segments and are really only at maximum efficiency for part of each level cruise leg. [Note that when looking at the efficiency of cruise climb you need to include the potential energy gained over the cruise climb duration and its release as kinetic energy in the descent. Do not just look at the fuel flow during the cruise climb.]

As more airspace becomes 'free route' and allows 'business trajectories' that do not follow route structures (. e.g the North Atlantic OTS is due to disappear very soon.) expect the support tools for the controllers to be improved so the procedural block clearances will become less necessary. So brush up on engine performance in the cruise you can save a lot of fuel.

GlenQuagmire
30th Nov 2018, 21:16
When I have been issued a block clearance I use the phrase in the block FL430-490 and donít refer to my current altitude. I donít really know if thatís exactly right but I copied it from an American pilot I flew with (super bloke even though he later voted for Trump) and it seems to work. I have only ever been given block altitudes in European airspace by military controllers when conducting air tests, never for enroute.

I would like to add that American beer is not so bad that I refuse to drink it - I would simply like to find a pint of Hobgoblin or Bishops Finger in a bar in downtown LA one night. It would make me happy..

A Squared
30th Nov 2018, 22:30
When I have been issued a block clearance I use the phrase in the block FL430-490 and donít refer to my current altitude. I donít really know if thatís exactly right but I copied it from an American pilot I flew with (super bloke even though he later voted for Trump) and it seems to work. I have only ever been given block altitudes in European airspace by military controllers when conducting air tests, never for enroute.


In FAA land, the specified phraseology for issuing a block clearance is: MAINTAIN BLOCK (altitude) THROUGH (altitude) So I use pretty much that "Maintaining Block 10,000 through 14,000" "IN the Block XXX-YYY" is common too. Agree that it's best not to report the specific altitude you're occupying at the time, and It could lead to misunderstanding if the block altitude clearance is forgotten or not passed on to a subsequent controller.

Airmann
1st Dec 2018, 03:57
In FAA land, the specified phraseology for issuing a block clearance is: MAINTAIN BLOCK (altitude) THROUGH (altitude) So I use pretty much that "Maintaining Block 10,000 through 14,000" "IN the Block XXX-YYY" is common too. Agree that it's best not to report the specific altitude you're occupying at the time, and It could lead to misunderstanding if the block altitude clearance is forgotten or not passed on to a subsequent controller.


For ATC your current level while in a block is irrelevant. They need to know the block levels as you have full authority to climb and descend as you please within it with no requirement to inform them. They need to keep all other traffic clear of the entire block.

A Squared
1st Dec 2018, 04:00
For ATC your current level while in a block is irrelevant. They need to know the block levels as you have full authority to climb and descend as you please within it with no requirement to inform them. They need to keep all other traffic clear of the entire block.

Agreed, the important information for them is the limits of you clearance. Stating your current altitude doesn't really add anything useful and might foster a misunderstanding.

Rick777
1st Dec 2018, 04:42
Block altitudes are used all thme time by the military for air refueling and large airplanes in formation.

misd-agin
1st Dec 2018, 20:22
Block altitudes are used all thme time by the military for air refueling and large airplanes in formation.

And large formations. Tankers, and their 'chicks in tow', can be at different altitudes within the block.

tdracer
1st Dec 2018, 21:19
Block altitudes were pretty common when we were doing flight testing at Boeing - although they'd frequently banish us to some little used airspace off the Pacific Coast to do it.
According to the propulsion theory I was taught in college 40+ years ago, the most fuel efficient cruise was a so called "climbing cruise" - set thrust to maintain speed/altitude, then leave the throttle fixed and let the aircraft gradually climb as it burns off fuel and gets lighter. Unfortunately not particularly practical in the real world, but it you can get a block altitude it could work...
BTW, the trick to finding good beer in the US is to avoid the mass-market beers. There are many fine 'micro-brews' or 'craft breweries' and/or 'brew pubs'. Also, avoid lagers if you can. IPAs have become very popular with the craft beer crowd and I don't think any of the mass-market breweries market an IPA (unfortunately for me, I don't particularly care for IPAs).

A Squared
2nd Dec 2018, 02:37
IPAs have become very popular with the craft beer crowd and I don't think any of the mass-market breweries market an IPA (unfortunately for me, I don't particularly care for IPAs).

You too? I thought I was the only one.