Sir: Sam Boote is premature in condemning aviation to death when the oil runs out (Letters, 20 December). He is wrong to say the "hydrogen-fuelled jet engine is not even a gleam in anyone's eye".
In fact, according to www.bl.uk/collections/patents/greenaircraft.html, the first hydrogen-powered jet flew in 1956. Russia continued experiments, and Project Cryoplane began again in 2000, in collaboration with the EU. It is not the engine but fuel storage and management that is the major obstacle.
The ecological problem we face is a technical one, not a political one. Many a green would have us give up on technology and relinquish the liberty and prosperity it has brought. That is politically untenable. What is needed politically is a regulatory framework that brings adequate incentive to the development of sustainable technology. A suitable charge on the consumption of all finite resources would be a good beginning.
DR IAN EAST
Sir: The feasibility of hydrogen-fuelled civil aviation was demonstrated in the late 1970s when Lockheed prepared a design for a liquid hydrogen-fuelled version of the TriStar airliner. The main design change was a stretched fuselage to accommodate the liquid hydrogen tanks, which could not be held in the wings.
At the time, the motivating factor was the increasing cost of oil. Hydrogen can be produced from natural gas; had the price of oil risen just a little further in 1979, hydrogen would have become a more cost-effective aviation fuel than kerosene.
The prospect of a zero-carbon-emissions airliner when the oil does run out may not appeal to those opposed to aviation, but pragmatic environmentalists should see it as a reasonable compromise.
BOB J WALSH
ROTHERHAM, SOUTH YORKSHIRE
Heathrow issue is clouded over
Sir: Simon Calder is clouding the issue when he argues that Heathrow should be expanded or it will lose out to Frankfurt, Paris and Amsterdam, all of which have more runways (article, 21 December).
He is not comparing like with like. The correct procedure would be to compare all London's airports with the all the airports serving the other cities. When this is done, a very different picture emerges.
The figures show that London's airports (Heathrow, Gatwick, Stansted, Luton and London City) are way ahead of their rivals in terms of passenger use.
In 2004, 128 million passengers used London's airports, more than any other city in the world. Paris, London's closest European rival, was in fifth place with 73 million passengers. Frankfurt and Amsterdam were out of the top 10 with 51 and 45 million passengers respectively. What is more, in the preceding 10 years, London actually increased its lead over both Paris and Frankfurt.
Is Simon Calder seriously suggesting we build a third runway at Heathrow to cater for foggy days, now a rare occurrence?
CHAIR, HACAN CLEARSKIES, LONDON SW9
Sir: Three years ago, bound for Washington via New York, I was stranded in fog and snow at JFK. My connecting flight cancelled, I experienced a very different experience to that of travellers stuck this week at Heathrow, as described by Simon Calder.
No courteous airline staff to help me at JFK: American Airlines effectively washed their hands of any further responsibility for their passengers. No courtesy coaches to my destination not even courtesy buses into the city.
No information, no help-line, and no courtesy hotel accommodation. Worse still, no hotels at JFK and no train or metro system to enable any escape from that ghastly chaos. Amusing then for me to read Calder's implied criticism of BA's arrangements for 3,000 hotel rooms and alternate road transport provisions.
Airport delays are always unwelcome but let us not be too harsh on BA; they run a brilliant operation.
WOODFORD GREEN, ESSEX
Sir: As part of the 51 per cent of the population who did not take a flight this year, I cannot help but find a beautiful irony in fog grounding hundreds of planes at Heathrow ("A sorry story that highlights the flaw in aviation policy", 22 December).
How nice to see the climate wrecking flights for a change, rather than, as usually happens, flights wrecking the climate.
Steady progress in tsunami help
Sir: We read with interest Paul Vallely's article "What happened to the money raised to help victims of the Asian tsunami?" (21 December).
The global response to the tsunami showed us what the world can do when it pulls together. Children's lives were saved and are being rebuilt. No child died from a preventable disease in the aftermath of the tsunami. Public support made it possible for Unicef to respond quickly, sustain that response over the past two years and to continue its work.
It would be easy to build quickly and poorly. Through experience, Unicef knows that to achieve the best results for those affected by the tsunami involves good planning, talking to communities and co-operation from other agencies. Successful reconstruction takes time. Unicef has striven to meet its responsibility to move quickly, and ensure our work has lasting impact.
But recovery is not happening as quickly as we would like, much as the people affected by the tsunami need to return to their lives. Rebuilding shattered communities is a matter of steady commitment over many years.
COMMUNICATIONS DIRECTOR, UNICEF UK, LONDON WC2
Strict French rules of engagement
Sir: In your leading article on Darfur (20 December), you stated that, in the Central African Republic (CAR), "reports from the ground say the [French] operation has had a devastating impact on civilians". This allegation is unacceptable.
France is in that region, which is suffering from the Darfur crisis, to reinforce security and stability. The Mirage operation was conducted at the request of the CAR authorities, in support of their forces and other African troops, who operate under a mandate from the African Union.
The purpose was to destroy heavy weaponry (mortars and 14.5mm machineguns) which had been targeting CAR forces. It was mounted under the French forces' extremely strict rules of engagement. Thanks to this operation, civilians who had fled to avoid the rebels' brutality have now returned to their village. In a situation as tragic as Darfur, serious allegations should not be made lightly.
FRENCH AMBASSADOR TO THE UNITED KINGDOM, LONDON SW1
How children should learn languages
Sir: Dr Stephen Bax is right to point out Toby Smith's "cosy fallacy" of young children automatically faring better in foreign languages (Letters, 19 December).
One problem which must be addressed is that of progression. Children with three years of study behind them must not stop while beginners catch up. Another common fallacy is that of the single method, an unrealistic reliance on IT, or the grammar-grind, the language laboratory, the aural/ oral method, the no-writing one.
Hearing, reading, writing and speaking a foreign language, and developing a sound grasp of grammar, exercise different parts of the brain. To be equipped for long-term language-learning, a full range of approaches and methods must be used.
Blame poverty, not the lone parents
Sir: We challenge the assumption ("Family values are back in the political arena", Leading article, 11 December) of a consensus that family breakdown is the cause of all Britain's ills. There is no proven causal link between lone parenthood and long-term poorer outcomes for children. But there is extensive evidence of the damaging effects of poverty.
Family breakdown and poverty need not be inextricably linked. Denmark, for instance, with a similar rate of lone parenthood to Britain, has the lowest child-poverty rate in the EU. A married couple's tax allowance would deepen the relative disadvantage faced by one-parent families and would not tackle poverty.
We welcome the Conservative recognition that lone parenthood "is rarely a lifestyle choice", but lone parents will reserve judgement on whether the Tory war on them is over until they see policies for tackling low income and deprivation, whatever the family type.
CHIEF EXECUTIVE, ONE-PARENT FAMILIES, LONDON NW5
Welcome news for our museums
Sir: I am glad to be able to reassure your readers and David Lister ("The Week in Arts", 16 December), that the good news that 43 per cent of the population have visited a museum or gallery this year is a National Statistic based on a national survey commissioned by Department for Culture, Media and Sport.
He is right that simple museum visitor figures may include people who visit several times. But the 43 per cent figure is based on a sample of 28,117 households in England carried out by BMRB to establish how many people visited museums and galleries at least once in the preceding year.
Is it lamentable, as he suggests, that only 43 per cent of people have entered museum and gallery doors? We don't think so. We would like everyone to be a visitor but museums and galleries are not for everyone as, for example, football is not for everyone (a MORI poll suggests only 41 per cent of people have any interest in football).
What is encouraging is that so many more people have discovered the pleasures and joys of museums and galleries over the past few years, helped by free admission and huge interest in art and design, which is vital to our booming creative economy.
A similar survey in 1999 showed that just 35 per cent of the population visited a museum or gallery once a year.
CHAIRMAN, NATIONAL MUSEUM DIRECTORS' CONFERENCE DIRECTOR, VICTORIA AND ALBERT MUSEUM, LONDON SW7
Empty threat to the jobless young
Sir: Sir: A report from the Home Office on crime becoming the career of choice for the young men of the inner cities follows hard on the heels of the Secretary of State for Work and Pensions threatening to stop the benefits of the long-term unemployed to get them into work.
They already go without if they fail to turn up at a job interview, and life is little different when the benefits are reinstated at £34.60 a week at 17 and under, £45.50 at 18 to 24 and £57.45 for single, childless adults aged between 25 and 60, all rates to be increased by £1.05, £1.35 and £1.70 a week in April. Many do not apply because the money is not worth the hassle in a very expensive economy.
John Hutton believes he is driving them all into legitimate work, much of which is poverty-paid, but other sources of income are found; the Asbos proliferate and more and more prisons are built.
So the threat to stop benefits that are already painfully inadequate, or non-existent, will be ridiculed on the streets of Britain.
REV PAUL NICOLSON
CHAIRMAN, ZACCHAEUS 2000 TRUST, LONDON N17
The birds ...
Sir: As we prepare for Christmas, outside my front window I can see a pair of collared doves building a nest. Is this normal behaviour for doves at this time of year? Is it a sign of peace and goodwill? Or is it another example of global warming?
... and a bee ...
Sir: I was surprised to see today (21 December) that our winter-flowering honeysuckle was not "wasting its sweetness on the desert air" but was entertaining a large bumble bee.
COLIN V SMITH
ST HELENS, MERSEYSIDE
... and the flowers
Sir: The implications of global warming are certainly alarming ("Do they know it's Christmas?", 18 December). But I must say that the sight of two bougainvillaea shrubs furiously blooming in our south-facing, unheated conservatory makes a unusual and colourful display at this time of the year.
The frozen limit
Sir: The article on sulphites (19 December) and the statement "Sulphites are used liberally on frozen potatoes, which are often used to make chips" suggests all frozen potato-product manufacturers use them. We are Britain's leading UK potato-product manufacturer, and the safety and quality of our products is one of most important factors for us. Like many of our peers, we do not use sulphites; we use just the humble potato and sunflower oil.
McCAIN FOODS (GB) LTD, SCARBOROUGH, NORTH YORKSHIRE
Pray for understanding
Sir: Margaret Beckett's inarticulate nonsense about whether the war in Iraq has made the world a better place (Comment, 20 December) was a model of clarity compared to the response of the Archbishop of York, John Sentamu, when asked to provide evidence for the existence of God (article, 18 December), "The 'evidence' lies in our readiness to have our fixed assumptions questioned and judged by that which lies at the centre of faith". Anyone care to hazard a guess what on earth that might mean?
D J O'BOYLE
Where it belongs
Sir: I was delighted to be featured in "My Week" (16 December). But I am director of broadcast and programming at Unique Media which makes, amongst other programmes, The British Comedy Awards. I am not its director, producer, head cook, bottle-washer or claimer of credit for the work which our excellent production teams achieve. It may be the Christmas break, but I am hoping to work with these people again in the new year.
It's a bargain
Sir: Could we not extend copyright for musicians to 90 years in exchange for Slade not being played at Christmas?