5 ms·

I wonder if one could build a couple of aircraft carrier for commercial airliners and post them out in the Pacific somewhere to get shorter ETOPS-compliant flig

I wonder if one could build a couple of aircraft carrier for commercial airliners and post them out in the Pacific somewhere to get shorter ETOPS-compliant flight paths. I also wonder how much fuel is spent carrying fuel and if emissions wouldn't be lower if they would fly shorter legs on fumes and do frequent refueling stops.

iancmceachern 5y ago
It's not as if the navy airplanes that take off and land from carriers are standard issue planes. There are very specific, pretty risky tech that goes into each catapult launch, arrested landing, etc. Doing so in an airliner full of passengers would be too risky in my view. Not to mention the size of aircraft carrier that would be required to land even a 737.
weberer 5y ago
There is no possible way that a commercial airliner can land on an aircraft carrier.
- adhesive_wombat 5y ago
  They can definitely touch down on one. They just can't also come to a stop on the same one, or even get to the other end with both wings attached. Though if you fitted a tail hook to a 747, probably some of that 747 could be said to have landed there. Maybe a few passengers too, and you could claim the fastest disembarkation speeds into the bargain. Turnaround times might suffer depending on the depth of the water.
- jamiek88 5y ago
  It’s humorous really. Such a massive misunderstanding of scale.
  - jacquesm 5y ago
    It's straight into 'how many programmers does it take to change a lightbulb?' territory.
thombat 5y ago
Minimum runway length quoted for Boeing 777 take-offs is 2500m, plus a 240m runway end safety area (a sandpit it can plow into if the takeoff is aborted without remaining space to halt). On an aircraft carrier this might be shortened a little since the ship can steam into whatever wind is present, but compare that to the 333m long flight deck on the new Gerald Ford class aircraft carriers and the impossibility is plain to see.
- mrec 5y ago
  I wonder what the limits are on how far something like https://en.wikipedia.org/wiki/Project_Habakkuk https://en.wikipedia.org/wiki/Project_Habakkuk could be scaled up.
  - thombat 5y ago
    Habakkuk sounds like many a run-away software project, where a promising notion keeps being pursued long before its impracticability is apparent. Gems from that wiki link: * The final design of Habakkuk II gave the bergship, as it was called, a displacement of 2.2 million tons * The small prototype built in 1944 on a Patricia Lake near Jasper, Alberta, confirmed the researchers' forecast that the full-size vessel would cost more money and machinery than a whole fleet of conventional aircraft carriers * [Assistant Controller of Research and Development for the Admiralty during the Second World War] pointed out the large amount of wood pulp that would be required was enough to affect paper production significantly. He also claimed that each ship would require 40,000 tons of cork insulation, thousands of miles of steel tubing for brine circulation and four power stations, but that for all those resources (some of which could be used to manufacture conventional ships of more effective fighting power) Habakkuk would be capable of travelling at only 6 knots (11 km/h) of speed. * the enormous amount of steel needed for the refrigeration plant that was to freeze the pykrete was greater than that needed to build the entire carrier of steel * the crucial argument was that the rapidly increasing range of land-based aircraft rendered floating islands unnecessary And that behemoth was required for a runway half as long as current civil airliners need.
- RcouF1uZ4gsC 5y ago
  Also the aircraft landing on a carrier have tail hooks to stop themselves and an undercarriage that is designed for those stresses.
jacquesm 5y ago
No. Really, I have no idea if this comment was in jest or halfway serious but there isn't any way passenger planes will ever land on any of the existing aircraft carriers. Width, Runway length, arrestor strength, inability to do cat launches with something that heavy and so on. It isn't going to happen.
- jeromegv 5y ago
  That’s when you know the technical conversation in this thread will go nowhere. That’s the solution? Aircraft carriers? Really? Some tech people do have a strong sense of entitlement about how easy some problems are to solve.
  - adhesive_wombat 5y ago
    Landing a passenger jet on an aircraft carrier really would be "moving fast and breaking things".
    - jacquesm 5y ago
      Including aircraft carriers... 63 meter wingspan for a 777 vs 40 meters for a C130, flight deck width of an aircraft carrier is about 80 meters so in theory that is possible but it would be pretty scary, I don't know of any airport where there is an obstacle the size of an 8 floor building sitting right next to the runway.
adamjb 5y ago
They successfully tested landing and taking off a loaded C-130 from a carrier in the 60s so I guess if you designed a new long range STOL airliner from the ground up it wouldn't be impossible and might even have a slim slim chance of being economical. But existing airliners, no way. And with the risks of carrier operations I don't reckon it'd be anywhere near as safe as 6 hour ETOPS. https://www.youtube.com/watch?v=ar-poc38C84 https://www.youtube.com/watch?v=ar-poc38C84
- jacquesm 5y ago
  The risk analysis alone makes it a non-starter, besides the fact that such airliners don't exist, a C130 vs a 777 is a huge difference in size, weight, range and take-off speed (80 tons vs 200 tons, 2500 nm vs 5000 nm minimum), 130 kph vs 240 kph. The C130 has four prop-jets, the 777 is a dual turbofan. Payload for a 777 is about 100 tons, C130 landing on that carrier was 12 tons. And as for that test: there is a reason it was left at the 'test' stage, it was deemed too risky. It is amazing that they managed to land a C130 on an aircraft carrier at all, even more amazing that they did it 30 times or so without mishap, but it is a very, very long stretch away from being able to land a passenger jet and take off again routinely, what is acceptable risk for the navy would never fly (pun intended) for passenger service.
United857 5y ago
> I wonder if one could build a couple of aircraft carrier for commercial airliners and post them out in the Pacific somewhere to get shorter ETOPS-compliant flight paths. The various Pacific Islands like Hawaii, Guam, Midway, the Aleutians are effectively those "carriers" for ETOPS.
sbalea 5y ago
To your first point, you cannot operate a commercial airliner from a carrier, for a multitude technical reasons. That being said, I seem to remember that, back in the day, the Navy would post ships at various remote points in the Pacific ocean to be there in case airliners had to ditch. To your second point, yes, to some extent it would be more efficient to make refueling stops, but you need conveniently located airports, and all those landings and takeoffs add to the duration of the flight and to the stress on the airplane, so it has to be balanced.

iancmceachern 5y ago

It's not as if the navy airplanes that take off and land from carriers are standard issue planes. There are very specific, pretty risky tech that goes into each catapult launch, arrested landing, etc. Doing so in an airliner full of passengers would be too risky in my view. Not to mention the size of aircraft carrier that would be required to land even a 737.

weberer 5y ago

There is no possible way that a commercial airliner can land on an aircraft carrier.

adhesive_wombat 5y ago
They can definitely touch down on one. They just can't also come to a stop on the same one, or even get to the other end with both wings attached. Though if you fitted a tail hook to a 747, probably some of that 747 could be said to have landed there. Maybe a few passengers too, and you could claim the fastest disembarkation speeds into the bargain. Turnaround times might suffer depending on the depth of the water.
jamiek88 5y ago
It’s humorous really. Such a massive misunderstanding of scale.
- jacquesm 5y ago
  It's straight into 'how many programmers does it take to change a lightbulb?' territory.

thombat 5y ago

Minimum runway length quoted for Boeing 777 take-offs is 2500m, plus a 240m runway end safety area (a sandpit it can plow into if the takeoff is aborted without remaining space to halt). On an aircraft carrier this might be shortened a little since the ship can steam into whatever wind is present, but compare that to the 333m long flight deck on the new Gerald Ford class aircraft carriers and the impossibility is plain to see.

mrec 5y ago
I wonder what the limits are on how far something like https://en.wikipedia.org/wiki/Project_Habakkuk https://en.wikipedia.org/wiki/Project_Habakkuk could be scaled up.
- thombat 5y ago
  Habakkuk sounds like many a run-away software project, where a promising notion keeps being pursued long before its impracticability is apparent. Gems from that wiki link: * The final design of Habakkuk II gave the bergship, as it was called, a displacement of 2.2 million tons * The small prototype built in 1944 on a Patricia Lake near Jasper, Alberta, confirmed the researchers' forecast that the full-size vessel would cost more money and machinery than a whole fleet of conventional aircraft carriers * [Assistant Controller of Research and Development for the Admiralty during the Second World War] pointed out the large amount of wood pulp that would be required was enough to affect paper production significantly. He also claimed that each ship would require 40,000 tons of cork insulation, thousands of miles of steel tubing for brine circulation and four power stations, but that for all those resources (some of which could be used to manufacture conventional ships of more effective fighting power) Habakkuk would be capable of travelling at only 6 knots (11 km/h) of speed. * the enormous amount of steel needed for the refrigeration plant that was to freeze the pykrete was greater than that needed to build the entire carrier of steel * the crucial argument was that the rapidly increasing range of land-based aircraft rendered floating islands unnecessary And that behemoth was required for a runway half as long as current civil airliners need.
RcouF1uZ4gsC 5y ago
Also the aircraft landing on a carrier have tail hooks to stop themselves and an undercarriage that is designed for those stresses.

jacquesm 5y ago

No. Really, I have no idea if this comment was in jest or halfway serious but there isn't any way passenger planes will ever land on any of the existing aircraft carriers. Width, Runway length, arrestor strength, inability to do cat launches with something that heavy and so on. It isn't going to happen.

jeromegv 5y ago
That’s when you know the technical conversation in this thread will go nowhere. That’s the solution? Aircraft carriers? Really? Some tech people do have a strong sense of entitlement about how easy some problems are to solve.
- adhesive_wombat 5y ago
  Landing a passenger jet on an aircraft carrier really would be "moving fast and breaking things".
  - jacquesm 5y ago
    Including aircraft carriers... 63 meter wingspan for a 777 vs 40 meters for a C130, flight deck width of an aircraft carrier is about 80 meters so in theory that is possible but it would be pretty scary, I don't know of any airport where there is an obstacle the size of an 8 floor building sitting right next to the runway.

adamjb 5y ago

They successfully tested landing and taking off a loaded C-130 from a carrier in the 60s so I guess if you designed a new long range STOL airliner from the ground up it wouldn't be impossible and might even have a slim slim chance of being economical. But existing airliners, no way. And with the risks of carrier operations I don't reckon it'd be anywhere near as safe as 6 hour ETOPS. https://www.youtube.com/watch?v=ar-poc38C84 https://www.youtube.com/watch?v=ar-poc38C84

jacquesm 5y ago
The risk analysis alone makes it a non-starter, besides the fact that such airliners don't exist, a C130 vs a 777 is a huge difference in size, weight, range and take-off speed (80 tons vs 200 tons, 2500 nm vs 5000 nm minimum), 130 kph vs 240 kph. The C130 has four prop-jets, the 777 is a dual turbofan. Payload for a 777 is about 100 tons, C130 landing on that carrier was 12 tons. And as for that test: there is a reason it was left at the 'test' stage, it was deemed too risky. It is amazing that they managed to land a C130 on an aircraft carrier at all, even more amazing that they did it 30 times or so without mishap, but it is a very, very long stretch away from being able to land a passenger jet and take off again routinely, what is acceptable risk for the navy would never fly (pun intended) for passenger service.

United857 5y ago

> I wonder if one could build a couple of aircraft carrier for commercial airliners and post them out in the Pacific somewhere to get shorter ETOPS-compliant flight paths. The various Pacific Islands like Hawaii, Guam, Midway, the Aleutians are effectively those "carriers" for ETOPS.

sbalea 5y ago

To your first point, you cannot operate a commercial airliner from a carrier, for a multitude technical reasons. That being said, I seem to remember that, back in the day, the Navy would post ships at various remote points in the Pacific ocean to be there in case airliners had to ditch. To your second point, yes, to some extent it would be more efficient to make refueling stops, but you need conveniently located airports, and all those landings and takeoffs add to the duration of the flight and to the stress on the airplane, so it has to be balanced.