FL430 for commercial airliners

[Rockie]

Maybe you should have searched for 3 minutes.

I’m always confused by some posts where it seems like the author doesn’t care if what they post is accurate. They just take their best guess. The rule in the US changed last year. Took 2 min of searching to verify.

Summary
This action amends the oxygen mask requirement for circumstances in which a single pilot is at the aircraft controls. This action applies to all certificate holders who conduct domestic, flag, and supplemental operations. This action responds to a statutory mandate that requires the FAA to increase the flight level threshold at which the FAA requires use of an oxygen mask by the remaining pilot at the aircraft controls when the other pilot at the controls leaves the control station.
Dates
This final rule is effective on March 23, 2020.
For Further Information Contact
Daniel T. Ronneberg, Part 121 Air Carrier Operations, Air Transportation Division, Flight Standards Service, Federal Aviation Administration, 800 Independence Avenue SW, Washington, DC 20591; telephone <a href="tel:202-267-1216">202-267-1216</a>; email Dan.Ronneberg@faa.gov.
Supplementary Information
I. Executive Summary
This final rule addresses section 579 of the Federal Aviation Administration Reauthorization Act of 2018, Public Law 115-254 (Oct. 5, 2018) (“FAARA 2018”), which requires the FAA to issue a final regulation revising § 121.333(c)(3) of title 14, Code of Federal Regulations (14 CFR), to apply only to flight altitudes above flight level 410. Such an amendment would increase the flight level  (1) threshold from flight level 250 to flight level 410 (i.e., a flight altitude of 41,000 feet), at which the FAA requires a pilot at the controls to put on and use the required oxygen mask while the other pilot leaves his or her control station. As a result, by this action, the FAA amends 14 CFR 121.333(c)(3) to replace the current flight altitude threshold of flight level 250 with flight level 410.

https://www.regulations.gov/document?D ... -0289-0001

[BTD]

Apologies guys. I cast too wide of a net on my previous post. It was in reference to Rockie’s “I’m sure in the US it is the same” remark. Which is about as good as “I don’t know”.

And Rockie, why should I have taken 3 min? Was my reference incorrect? Is part 121 not commercial air carrier regulations in the US which is precisely what was asked by NotDirty?

[wallypilot]

Because 430 isn't an RVSM altitude. You would need a block altitude to operate at FL430.

Not entirely true or logical statement.

[BTD]

I’m always confused by some posts where it seems like the author doesn’t care if what they post is accurate. They just take their best guess. The rule in the US changed last year. Took 2 min of searching to verify.

Summary
This action amends the oxygen mask requirement for circumstances in which a single pilot is at the aircraft controls. This action applies to all certificate holders who conduct domestic, flag, and supplemental operations. This action responds to a statutory mandate that requires the FAA to increase the flight level threshold at which the FAA requires use of an oxygen mask by the remaining pilot at the aircraft controls when the other pilot at the controls leaves the control station.
Dates
This final rule is effective on March 23, 2020.
For Further Information Contact
Daniel T. Ronneberg, Part 121 Air Carrier Operations, Air Transportation Division, Flight Standards Service, Federal Aviation Administration, 800 Independence Avenue SW, Washington, DC 20591; telephone 202-267-1216; email Dan.Ronneberg@faa.gov.
Supplementary Information
I. Executive Summary
This final rule addresses section 579 of the Federal Aviation Administration Reauthorization Act of 2018, Public Law 115-254 (Oct. 5, 2018) (“FAARA 2018”), which requires the FAA to issue a final regulation revising § 121.333(c)(3) of title 14, Code of Federal Regulations (14 CFR), to apply only to flight altitudes above flight level 410. Such an amendment would increase the flight level  (1) threshold from flight level 250 to flight level 410 (i.e., a flight altitude of 41,000 feet), at which the FAA requires a pilot at the controls to put on and use the required oxygen mask while the other pilot leaves his or her control station. As a result, by this action, the FAA amends 14 CFR 121.333(c)(3) to replace the current flight altitude threshold of flight level 250 with flight level 410.

https://www.regulations.gov/document?D ... -0289-0001

I posted a part 91 reference, you posted a part 121 reference, that's where I made the mistake in my second post.

Also, you're reference talks about leaving ones seat... all it says there is that when one crew member leaves, the other doesn't need to put their mask on unless they are above flight level 410

https://www.ecfr.gov/cgi-bin/text-idx?S ... 3&rgn=div8

Part 121.333

"(a) General. When operating a turbine engine powered airplane with a pressurized cabin, the certificate holder shall furnish oxygen and dispensing equipment to comply with paragraphs (b) through (e) of this section in the event of cabin pressurization failure.

(b) Crewmembers. When operating at flight altitudes above 10,000 feet, the certificate holder shall supply enough oxygen to comply with §121.329, but not less than a two-hour supply for each flight crewmember on flight deck duty. The required two hours supply is that quantity of oxygen necessary for a constant rate of descent from the airplane's maximum certificated operating altitude to 10,000 feet in ten minutes and followed by 110 minutes at 10,000 feet. The oxygen required in the event of cabin pressurization failure by §121.337 may be included in determining the supply required for flight crewmembers on flight deck duty.

(c) Use of oxygen masks by flight crewmembers. (1) When operating at flight altitudes above flight level 250, each flight crewmember on flight deck duty must be provided with an oxygen mask so designed that it can be rapidly placed on his face from its ready position, properly secured, sealed, and supplying oxygen upon demand; and so designed that after being placed on the face it does not prevent immediate communication between the flight crewmember and other crewmembers over the airplane intercommunication system. When it is not being used at flight altitudes above flight level 250, the oxygen mask must be kept in condition for ready use and located so as to be within the immediate reach of the flight crewmember while at his duty station.

(2) When operating at flight altitudes above flight level 250, one pilot at the controls of the airplane shall at all times wear and use an oxygen mask secured, sealed, and supplying oxygen, in accordance with the following:

(i) The one pilot need not wear and use an oxygen mask at or below the following flight levels if each flight crewmember on flight deck duty has a quick-donning type of oxygen mask that the certificate holder has shown can be placed on the face from its ready position, properly secured, sealed, and supplying oxygen upon demand, with one hand and within five seconds:

(A) For airplanes having a passenger seat configuration of more than 30 seats, excluding any required crewmember seat, or a payload capacity of more than 7,500 pounds, at or below flight level 410.

(B) For airplanes having a passenger seat configuration of less than 31 seats, excluding any required crewmember seat, and a payload capacity of 7,500 pounds or less, at or below flight level 350.

(ii) Whenever a quick-donning type of oxygen mask is to be used under this section, the certificate holder shall also show that the mask can be put on without disturbing eye glasses and without delaying the flight crewmember from proceeding with his assigned emergency duties. The oxygen mask after being put on must not prevent immediate communication between the flight crewmember and other crewmembers over the airplane intercommunication system.

(3) Notwithstanding paragraph (c)(2) of this section, if for any reason at any time it is necessary for one pilot to leave his station at the controls of the airplane when operating at flight altitudes above flight level 410, the remaining pilot at the controls shall put on and use his oxygen mask until the other pilot has returned to his duty station."

No Worries. It recently changed. In the executive summary of the post/link I included, it discusses that the threshold for oxygen masks if one pilot left their controls stations used to be FL250, but last year they changed it to FL410. So NotDirty was on track with his recollection.

[twa22]

Apologies guys. I cast too wide of a net on my previous post. It was in reference to Rockie’s “I’m sure in the US it is the same” remark. Which is about as good as “I don’t know”.

And Rockie, why should I have taken 3 min? Was my reference incorrect? Is part 121 not commercial air carrier regulations in the US which is precisely what was asked by NotDirty?

No worries, i'm glad you pointed it out actually, it made it simple to find the FAR reference regarding altitude and oxygen restrictions above FL410

[Rockie]

Apologies guys. I cast too wide of a net on my previous post. It was in reference to Rockie’s “I’m sure in the US it is the same” remark. Which is about as good as “I don’t know”.

And Rockie, why should I have taken 3 min? Was my reference incorrect? Is part 121 not commercial air carrier regulations in the US which is precisely what was asked by NotDirty?

[quote=NotDirty! post_id=<a href="tel:1142984">1142984</a> time=<a href="tel:1612466971">1612466971</a> user_id=44305]
[quote="New Antique Pilot" post_id=<a href="tel:1142975">1142975</a> time=<a href="tel:1612461176">1612461176</a> user_id=71086]
[quote=lhalliday post_id=<a href="tel:1142958">1142958</a> time=<a href="tel:1612455564">1612455564</a> user_id=48331]
I've always wondered about Concorde in this respect, either the regulations were different or there were things we just didn't see on the flight deck.

They also would have had ITAR issues with GPS navigation, but GPS wasn't a big thing in planes until after they were retired.

...laura

I had a short cockpit visit on the Concorde on a flight from LHR-JFK-OSH in 1985.
We were up around FL600 and no one was wearing a O2 mask.

NAP
[/quote]

I don’t suppose that the CARs (or ANOs in 1985) apply to a UK based airline flying to the USA.

IIRC the FARs have more restrictive O2 rules below 410, something about the PF had to don his/her mask if the other pilot left the flight deck above ~250.

Someone has said that O2 regs are probably the most frequently intentionally violated rules in the book. That doesn’t make it right, but not surprising.
[/quote]

It’s above 250 here without a quick donning mask, 410 with. I’m sure the US is the same.
[/quote]

You’re right BTD, I didn’t see the line about one pilot leaving the flight deck. Apologies. “I’m sure” however does not mean “I don’t know”. It means I’m sure but leaves open the possibility I could be wrong since I didn’t look up the reference myself.

[goldeneagle]

plus you'd be using up the crew O2 for normal ops instead of emergency and the aircraft bottles aren't that big.

Unless the aircraft is equipped with oxygen concentrators for the stations in question, then the supply is basically unlimited.

[Rockie]

plus you'd be using up the crew O2 for normal ops instead of emergency and the aircraft bottles aren't that big.

Unless the aircraft is equipped with oxygen concentrators for the stations in question, then the supply is basically unlimited.

I’ve never seen that in a commercial airliner. Are some of these high flying business jets equipped with it? That would make sense.

It’s also not just the supply of O2 but the lack of ambient pressure after an explosive decompression and what it does to the body. When I was in the military the airplane was capable of operating at much higher altitudes than we were permitted to go without a full pressure suit. I’d be interested in hearing the risk assessment calculus for high flying civil machines.

[SeawingsUAE]

O2 as mentioned above is the most un observed "rule" in current High level aviation, but it's not really the reason.
In reality for most aircraft to be at or close to their service ceiling requires them to be so light that they are either flying empty, (IE no payload) or they have burned the vast majority of their enroute fuel and are pretty close to TOD. If it's reason 1, that is (was) not usually the reality in commercial aviation, and if its reason two, for the most part there would be no gain to climb, knowing you were descending in the next 15-45 minutes.

As well, in some cases you can achieve a better mach lower, and it's worth trading a slightly higher burn for more speed, which means less overall burn due faster enroute time.