The British Airways captain ranks the worst weather conditions for flying

What is the worst weather to fly?

Captain Steve Allright leads British Airways’ Flying with Confidence course for nervous fliers and reveals in the fascinating companion book Flying With Confidence: The Proven Program To Fix Your Flying Fears (Random House UK) that this is a question he is often asked by attendees.

To help answer this, in the book he again rates the most potentially dangerous species out of 10 for their ability to cause distraction, based on his own personal experience and distraction stories from colleagues.

Read on for his ranking – ‘the higher the number, the more fuel I carry’.

Plus, there’s more information on flying in bad weather from Air Canada Dreamliner Captain Doug Morris’ book This Is Your Captain Speaking.

High temperatures (and/or high altitude airports). Redirect rating – zero out of ten

Captain Allright says, “When the air is very hot it becomes very ‘thin’ and the engines don’t run as efficiently and the wings don’t produce as much lift, the same effect as being at very high altitudes, as in Johannesburg (1753m) .

“We call these airfields ‘hot and high’ and while not dangerous, this combination poses a particular challenge to pilots. We just need a longer runway and we have to take into account the influence of the conditions on the performance of the aircraft.’

Captain Doug Morris goes on to explain that takeoff speeds are higher in these conditions, with pilots sometimes reducing weight – fewer passengers and less cargo – to ensure the plane takes to the air safely.

He writes: “Many airlines in the Middle East operate most of their flights in the wee hours of the night as temperatures are somewhat cooler. Fortunately for them, most airports are at sea level.’

Because of their high altitude, Captain Morris adds, Denver (5,434 ft/1,656 m) and Calgary (3,556 ft/1,083 m) have some of the longest airstrips in North America.

Ice. Redirect score – one out of 10

Captain Allright says, “There are two effects of ice, one on the ground and one in the air. To take off safely, the upper surface of the wing must be free of ice. For this reason, aircraft are regularly de-iced in the morning after frost and before each take-off. In the air, it is possible for ice to build up on the wings, usually at the leading edge, during flight through clouds when the air temperature is around freezing.

“All commercial aircraft have some sort of anti-icing and/or de-icing system on board, usually hot air drawn from the engine and directed along the leading edge of the wing.

“An icy runway wouldn’t be impossible to land on – airports in very cold climates often have heated runways.”

Captain Morris points out one of the positives for pilots in cold weather.

He writes: ‘Cold temperatures mean denser air, which is welcomed by every aviator. Cold air at -40C is about a third denser than hot air at 40C. Denser air produces more lift over the wings and flight controls, as well as more thrust from the engines and propellers.

“You’ll understand what pilots mean when they describe climbing performance as that of a “homesick angel.”

He adds that one of the challenges in cold weather is shipping livestock – “hairless cats and dogs are not allowed to travel in winter.”

Hail. Redirect score – one out of 10

Captain Allright says: ‘Hail is normally only associated with thunderstorms or rapidly accumulating clouds and so you would have to be flying in such a cloud to expose the aircraft to hail. While this is not impossible due to the constraints of busy airspace, it is extremely rare and usually only happens for a very short period of time. I’ve flown through hail a few times and other than being quite noisy in the cockpit, it has absolutely no effect on the plane. I’ve seen pictures of planes that suffered hail damage from extremely large dense hail, all of which landed safely.’

Heavy rain. Redirect score – one out of 10

Captain Allright says: ‘Modern aircraft engines can absorb an enormous amount of water, like flying through a dense rain cloud. The only real concern for pilots operating in heavy rain is a flooded runway. Even then, because aircraft are very directional stable on the ground and are additionally equipped with extremely effective anti-skid brakes, it would take a huge and sudden downpour to make a runway unsuitable for takeoff and landing.’

Captain Morris adds that a wet runway actually has a bonus for pilots – they make it easier to avoid a thump on landing.

Lightning. Redirect rating – two out of 10

Captain Allright says: ‘Lightning strikes are rare, but the aircraft is well designed to cope with such an event. In fact, the strike usually has no effect whatsoever on the usability of the aircraft. This is mainly because all aircraft are equipped with static fuses at the rear of the wing and tailplane. These are about the size of a long pencil and are specially designed to dissipate any excess static electricity that the aircraft can accumulate. Lightning strikes can be quite alarming as they usually result in a loud bang, but rest assured they will have little or no effect on the safety of the aircraft.’

Captain Morris adds that aircraft are struck by lightning about once a year and will be checked by engineers after that.

Fog. Redirect score – three out of 10

Fog isn’t dangerous or difficult for pilots to fly in, says Captain Allright, but it gets a three because it normally causes delays.

He continues: “Almost every modern airport has an Instrument Landing System (ILS) that allows aircraft to land safely, even in the most limited visibility.

‘[But] the usual distance between landing aircraft should be increased in low visibility operations.’

This, he explains, results in a reduced ‘flow rate’ and for aircraft to ‘hold on’ to a queuing system.

He adds, “If fog is predicted… many of us would consider extra fuel to last longer.”

Snow. Redirect score – three out of 10

Captain Allright says: ‘Snow is not a problem for aircraft in the air, but it can cause delays on the ground. For the same reason that ice needs to be removed from the wing, the same goes for snow. Heated de-icing fluid is used to remove any snow that has settled on the wing and then de-icing fluid is applied to create a “wait”, which prevents any more snow from settling on the wing.

‘Our pilots will also always perform a visual inspection from the cabin just before take-off to check whether the wing is still free.

“If you ever board an airplane that has been de-iced, you may notice that the applied liquid is green or orange. This is deliberate to indicate that it is still present. It may look quite “bulky” and again, this is normal.

“Landing on a snowy runway is not normal, but perfectly safe as long as the snow is compacted.

“The main problem with snow is that parking spaces can become limited because planes waiting to be de-iced occupy parking spaces that would otherwise be vacated.”

Strong wind. Redirect rating – four out of 10

Captain Allright says: ‘Strong winds are caused by many different types of weather and aircraft are well equipped to deal with them. Each aircraft type has its own limit, of course, usually around 70 mph or, if the wind happens to be over the runway, called a crosswind, closer to 50 mph.

“Taking off or landing in a crosswind can appear dramatic from the outside of the aircraft, but can also feel quite uncomfortable inside. Pilots are trained for this challenge and we get professional satisfaction from handling it safely.”

Captain Morris adds that it is “doable” to take off against a 100 mph wind blowing down the runway. “Getting to the runway would be the challenge,” he explains. “In addition, you have to think about ground operations and flying debris.”

Thunderstorms. Redirect rating – five out of 10

Captain Allright says, “Cumulonimbus cloud, or “Charlie Bravos,” CBs, as we call them, are probably the biggest challenge to a planned arrival. It is very unlikely that the flight crew will take off or land with a massive thunderstorm overhead due to the rapidly changing wind conditions, lightning strikes and heavy precipitation in the form of rain or hail.

Fortunately, commercial airliners are equipped with high-tech weather radar that detects this precipitation, enabling the flight crew to identify a thunderstorm more than 100 miles away and take action, day or night. It is possible to fly safely through a thunderstorm, and sometimes this is necessary due to the busy airspace. This will feel quite turbulent and uncomfortable in the cabin, but it’s perfectly safe. Thunderstorms are really only a problem if there is a major storm over an airport where you are trying to land. The wind around and under a thunderstorm can change speed and direction very quickly, changing the amount of lift produced by the wings.’

Fly with Confidence – The proven program to overcome your fear of flying (Random House UK) is now available.

To book yourself onto British Airways’ Flying with Confidence course, visit www.flyingwithconfidence.com. The day usually starts around 9am and is divided into morning sessions (technical) and afternoon sessions (psychology), followed by a BA jet flight with ongoing commentary from a pilot from the cockpit. The course is taught at London Heathrow, Gatwick, Edinburgh, Glasgow, Manchester, Dubai and Johannesburg. The courses at the last two locations are entirely on the ground, with no flight.

Steve Allright regularly runs the Heathrow course and was a British Airways Captain on the 757/767, 747 and now flies the 787. He has logged over 18,000 flying hours.

Coming Soon – MailOnline is joining the Flying With Confidence course to find out first hand how it helps nervous fliers.

This Is Your Captain Speaking by Captain Doug Morris is out now.