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Cut out taxying under power.

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Cut out taxying under power.

Old 3rd Dec 2006, 15:13
  #61 (permalink)  
 
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On a serious note, climate emissions are one of the two biggest threats to our industry (and all of us) right now.

Aviation creates a mere 1.6% of global CO2 emissions but you would think reading the media that it created 100%. Driving cars generates around 22% and heating our homes another 26%.

Taxing domestic emissions that every one of us alive contributes to is political suicide right now - taxing 'rich' air travellers (claims even that LCC pax are often second home owners) is politically encouraged and is percieved as acceptable.

In addition, these aviation taxes are being levied regionally not globally, creting regional competitive advantage and therefore less incentive to agree a global agreement by creating vested interests. If the UK stopped ALL CO2 emissions from all sources tomorrow for one year, it would only represent the equivalent of 3 months Chinese CO2 emissions. Green tax for all industries should be global and not regional.

In addition, none of the proposed green aviation taxes are invested back into CO2 reduction, just added to the overall Government tax receipts for building, among other things, more road infrastructure, one of the biggest CO2 sources. Green tax should be re-invested globally in finding solutions.

What does the aviation industry do in response to the media attacks? - very little, certainly in any co-ordinated way. IATA stands out as appearing particularly emasculated on this subject.

Virgin Group through both gestures such as this and their Gaia Investments are looking to;

a. Create an economic source of carbon neutral Butanol derived from bio mass to sell to airlines to power either current or future generations of aero engines.

b. Promote efficient use airspace to reduce emissions

c. Invest heavily in space travel technology. Before you shoot this down, realise that in 50 years if we want to continue mass travel, we will have to have found a transport solution that is outside our atmosphere. The space shuttle creates the same greenhouse gas emissions in one launch as New York City does in a month. Launching 6 people into space using Spaceship 2 will create the equivalent of one business class seat one way between London and New York and in theory could deliver you within 60 minutes to any point on the planet.

While Spaceship 2 is not the end answer, it is a significant step in that direction, and derives from the private sector at a cost to date of about USD12m - the equivalent cost of a single modern widebody aeroengine, a remarkable figure when compared to government sector achievements.

Let's congratulate Richard for both the long term investments and the short term gestures however practical they may / may not be - time will tell. He seems to be taking more action that any of us in this industry to secure the future for us all.
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Old 3rd Dec 2006, 15:30
  #62 (permalink)  
 
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Originally Posted by flying brain View Post
The space shuttle creates the same greenhouse gas emissions in one launch as New York City does in a month.
Not saying you're wrong, FB, but do you have a source for that statement ? Thanks.
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Old 3rd Dec 2006, 15:31
  #63 (permalink)  
 
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Well, this probably trumps my as yet unpatented idea to bank the taxiways leading to runway lineups.

Assuming no stops during the final taxi segment, my calculations had the 35 knot or so lineup groundspeed and resultant reduced energy expenditure saved during the initial takeoff roll leading to some "XXX" tonnes of reduced carbon emissions.

Of course, low friction coefficients during low winter ops require some tweaking of the idea...
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Old 3rd Dec 2006, 15:43
  #64 (permalink)  

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Chaos on the horizon?

I reckon this initially attractive idea would demand a high level of coordination from ATC, airfield designers and operators.

Starting engines out on the field without considering the rest of the infrastructure might just prove to be a bridge too far, especially when problems of the technical variety crop up.

It took a long time to get a good en-route de-icing procedure working at many airfields and even now each field has its own docking system, taxyway numbering system and so on. Before this goes to far I suggest that JAA and FAA coordinate a procedure which is standard across the world.

The manufacturers should be next in line, as a self towing aircraft (powered
mainwheels) would save a lot of machinery and manpower out in the sticks and possibly some fuel too.

FC.
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Old 3rd Dec 2006, 15:56
  #65 (permalink)  
 
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"Towing aircraft from a stand substantially reduces the amount of time they need to taxi with their engines running and reduces the time spent queuing before take-off," said Virgin Atlantic spokesman Paul Charles.

Prat! It doesn't reduce ANY time spent queuing for takeoff. You still have to load your pax at the terminal/stand AND get to the runway in use, AND WAIT YOUR TURN, with everybody else WHATEVER propulsive method you use. Good grief! Pie-in-the-sky nonsense.
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Old 3rd Dec 2006, 16:25
  #66 (permalink)  
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Originally Posted by MrBernoulli View Post
"Towing aircraft from a stand substantially reduces the amount of time they need to taxi with their engines running and reduces the time spent queuing before take-off," said Virgin Atlantic spokesman Paul Charles.

Prat! It doesn't reduce ANY time spent queuing for takeoff. You still have to load your pax at the terminal/stand AND get to the runway in use, AND WAIT YOUR TURN, with everybody else WHATEVER propulsive method you use. Good grief! Pie-in-the-sky nonsense.
Would that be a case of RTFQ?

Towing the aircraft out and either using a dedicated taxiway or a wide one to allow aircraft to be positioned to one side at say 45 degrees (unlikely) would work, but also getting the aircraft to start up as they reach the end of the queue, a short pause for the tug to disengage and leave by an access road then continue to the hold and off you go.

The idea is neither new or innovative. I've though it a good one for a while, and we only burn 200kg on the way out at LGW. For easterly departures from LHR, all that queuing for 9R would be a lot quieter and less polluting for T5 and that end of the airfield if most of the aircraft were sat there on APU and slowly being dragged along on tow, until they start up maybe three or four in from the end.

Best of luck to him.
 
Old 3rd Dec 2006, 16:48
  #67 (permalink)  
 
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Looks like industry is ahead of the game here. Check out this website here suggesting powered wheels.
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Old 3rd Dec 2006, 17:18
  #68 (permalink)  
 
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Why not have 4 length's of rope tied to the AC and get the Pax to pull the AC out. A foreman could sit atop an elephant with a whip in hand keeping them all in time. Total drivel by the master of the publicity stunt. What cars you driving chum,
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Old 3rd Dec 2006, 17:29
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Nothing new. Air France have been doing it for years at CDG.
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Old 3rd Dec 2006, 18:13
  #70 (permalink)  
 
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i've never seen an air france get towed out/power wheel pushed out to thr runway!!? they only use the power tug things to push back.
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Old 3rd Dec 2006, 18:53
  #71 (permalink)  
 
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Originally Posted by Fifty North View Post
Surely this is no more than cheap publicity stunt!
Is that not what he is all about ?

Can't see it working, LHR needs to run like clockwork, if he is holding up other A/C, it will cause an even worse scenario than there is now...

Brilliant idea - one which i'm sure many have thought of before - but cannot see it working in reality.

The amount of fuel worldwide used by taxying A/C must be phenomenal - i'm surprised no-one has found a realistic workable solution as yet - perhaps there isn't one........

Last edited by Anti-ice; 3rd Dec 2006 at 18:54. Reason: spellcheck
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Old 3rd Dec 2006, 18:58
  #72 (permalink)  
 
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<<Well, this probably trumps my as yet unpatented idea to bank the taxiways leading to runway lineups.

Assuming no stops during the final taxi segment, my calculations had the 35 knot or so lineup groundspeed and resultant reduced energy expenditure saved during the initial takeoff roll leading to some "XXX" tonnes of reduced carbon emissions.>>

Nice one, jonny. At least you brought a little light-hearted lunacy into the matter!
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Old 3rd Dec 2006, 19:05
  #73 (permalink)  
 
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Tip-towing tru the tulips

Seems as though the long distance towing and extra manoeuvering entailed in this scheme will put a LOT of new stress on nosegear pylons and related hardware, all of which are surely life-limited and rated for a less towing-intensive plan.

Probably will be necessary to factor in the negative fuel savings for an increase of departure fuel dumps on occasions when gear does not retract properly, etc.
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Old 3rd Dec 2006, 19:37
  #74 (permalink)  
 
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Would such an idea give rise to any issues of engines not being warmed up when cleared for take off, or can you just start these jets and go? i kind of assumed that they needed a few minutes to stabilise before being put to full power?
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Old 3rd Dec 2006, 19:48
  #75 (permalink)  
 
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Originally Posted by MarcJF View Post
Would such an idea give rise to any issues of engines not being warmed up when cleared for take off, or can you just start these jets and go? i kind of assumed that they needed a few minutes to stabilise before being put to full power?
You are potentially right. Not sure for a 400, but some Airbus engines (IAE) require 5 mins 'warm up' in some circumstances.

Also, I can really see places like LHR stopping all remote holding, so that the Bearded one can carry out this publicity stunt.
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Old 3rd Dec 2006, 19:56
  #76 (permalink)  
 
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Frankly, I'm glad to see someone has been even thinking about a solution to the problem that sees me burning 20% of the trip fuel just getting to the end of the runway.

Heathrow long ago stopped being fit for purpose, now just seeing 09R for departure equals 20mins late. There's just no hope.

If ever there was an M25 for aeroplanes
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Old 3rd Dec 2006, 20:06
  #77 (permalink)  
 
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Right - nothing new to the idea of dispatch / operational towing, how ever you want to call it.

BUT: With the fuel prices probably not getting cheaper in the long run AND upcoming laws concerning *local* emissions (i. e. around the airports!), it is certainly worth having a look at this idea again. I just think of the sometimes endless queues and taxi times at JFK for instance...

As for arcnizs comment: That is something that Boeing has answered for the B747 rather relaxed: Life limits hardly to be touched, additional inspections - yes. But nothing to worry about too much. No word from TLS so far.

Regards,
J.V.
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Old 3rd Dec 2006, 20:08
  #78 (permalink)  
 
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Why not use 09L because some !!!!!! in the 50's promised not to use it, so there is insufficent space at 09L threshold for taxiways, and T5 etc is in the way? or does Richard want T5 usage to save fuel?
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Old 3rd Dec 2006, 20:56
  #79 (permalink)  
 
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Seems to me the airports already have the answer. The baggage conveyor people have already worked out how to get luggage to move without its own power and get it round corners and everything, so why can't the baggage conveyor designers get let lose on the apron and come up with some nifty industrial-sized baggage conveyor between the stands and the threshold?
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Old 3rd Dec 2006, 21:29
  #80 (permalink)  
 
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quote

'Surely this is no more than cheap publicity stunt!'

What from the bearded one?

Whatever next, a balloon flight, a powerboat,a rocket flight,a lottery, and watch out those blokes with a big telecoms company who are far to big for anyone else to muscle in.

Does his island run on solar power- i think not.
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