Sunday, March 15, 2009


I don’t like flying.

I have a decent degree in Aeronautical Engineering from the 5th best University on the Planet. I’ve read and absorbed all the stats that tell me I’m safer flying in an aeroplane than I am driving to the airport. I also know that airline pilots don’t have their life insurance premiums loaded because of the hazardous nature of their jobs anymore than burger flippers in McDonalds do - actually I don't know if McDonalds burger flippers have increased Insurance premia, but you get my point.

In my defence, I have also flown solo several times in a 30 year old wooden glider, yanked 1000 feet up into the air by what looked like a (not very well) converted farm tractor. So, at least I've tried it.

But I still don’t like flying.

I still do it, because it used to be part and parcel of my job, and there are places in the world I want to visit, where any other way of getting there is almost unworkable. But my knuckles are a very pale shade of white for much of the time when we're buzzing along.

One of the things I do hope in my attempt to sleep well before a flight however is that the guys who police the Air Safety system are looking after my interests with unblinking vigilance. Mine (as in the passenger), and mine alone rather than the big businesses of the Aircraft Industry. They’re big enough and ugly enough to look after themselves in my view.

In the UK, we have the Civil Aviation Agency and the Air Accident Investigation Branch (AAIB). In Europe there is the European Aviation Safety Agency (EASA), and in America there is the National Transportation Safety Board (NTSB). You would like to think that, on safety matters, they all spoke with one voice, or at least you would find difficulty getting a cigarette paper between their views. We, the customers, rely on these guys to take the necessary decisions which might just keep us alive. It’s as simple as that.

Fast forward now to the Boeing 777, a two engined plane which has sold in many hundreds over the last few years. Its modern design, its massive level of economy and its slightly smaller size (compared to a 747 Jumbo) means that this plane is used increasingly in these straitened times as much as possible by the airlines who have them in their fleets. This aeroplane can be fitted with either Rolls Royce or General Electric Engines, and there is intense rivalry between both of these companies to power the next order that Boeing secure.

A couple of worrying “incidents” have occurred recently to two 777s, both powered by Rolls Royce engines – one a Delta plane in the USA, which lost power temporarily in one engine, and the other a BA plane which crash landed at Heathrow following a scary loss of power in both engines in the last stages of the approach.

Both incidents were apparently caused by the build up of ice particles in the fuel system, which blocked the flow of fuel through a heat exchanger thus resulting in a dramatic loss of power when power was what the pilot wanted above all else. No-one was killed in either incident, but, in the case of the Heathrow accident, this seemed to be because of prompt and responsive reactions from the pilot and God being on his side that day.

There seems no disagreement between anyone involved as to the cause of the accidents. If I’ve read it correctly, flying for a long time in a very cold environment seems to be the cause of the ice build up. If you read the AAIB report, the Trent (Rolls Royce) powered 777s have flown 6.5 million hours in total, and the Heathrow accident was the first time such a failure had occurred. It seems clear from the report that the flight temperatures experienced during the Heathrow flight were on the margins (70 out of 13,000) of the total RR 777 flights to date. But these "incidents" still should not have happened.

From my simple mind, one difficulty here is that the redundancy built into aircraft systems (for instance, 3 computer systems, with the aircraft taking the advice of the two good ones when the 3rd goes off the rails etc) doesn’t seem to work. If the environment outside can affect one engine system to the point where the ice builds up on the Heat exchanger inlet, then it’s not difficult to expect that a second engine situated a few yards to the left of that one is going to find itself in a similar situation. Even my conceptual, rhetorical discussion about whether the complexity of 4 engines outweighs the benefits offered by 2 engines goes out of the window here. If 2 engines can ice up, why shouldn’t 4? I’m still a believer in the More the Better from an engine point of view, but I'd rather that the engines kept running while the aeroplane was up in the air.

If you trawl through the AAIB’s report, and get to the summary, what you finds is as follows.

This is the first such event in 6.5 million flight hours and places the probability of the failure as being ‘remote’ as defined in EASA CS 25.1309.

Which seems to say that, in their eyes, this is an issue but not a major problem. That’s the UK (and Europe) speaking. And it conveniently passes the buck to the EASA in the event that, in the future, a Trent powered 777 falls out of the sky with serious results. But that report does not take into account the implications of the second Delta incident which occurred at a later date.

The problem starts when you get into the “What now?” bit of the discussion. Do you ground the Rolls 777 fleet until a sollution is in place? It would seem that Rolls needs some 12 months to design, test and certify and then manufacture and install the solution to the problem. In the meantime, Boeing and Rolls have issued a raft of operational changes which the airlines need to implement before they get the redesigned parts. These include periodic reductions and increases in engine power and the possible use of fuel additives. All of which increases the pilot workload, and could result in a catastrophic chain of events with no recovery, if such a problem occurred close to the ground.

The real issue here, from the wary and slightly knowledgeable passenger (ie Me), is – Is that response sufficient?

I’m not daft. I know that, even in the land of safety, everything has its price, including a human life. When last I looked, if it cost the aeroplane manufacturer less than c $2.75 million to save a life as a result of a design issue, they did it. If it cost more, they didn’t. Now I know it won’t be as simple as that, but you get my drift. There’s a cut off point, and in the aeroplane business, the scale of money is vast. So the money involved doesn’t just talk, it shouts. You don’t want it to be that way, but in truth, it can’t be any other way.

Hence you rely on the National Safety Boards to protect the passenger’s interests. Nationality, one would hope, doesn’t come into it. I’m not sure I’d trust a report from a West Indian Safety board to the same level as one from, say, Germany for instance. But, in the world of the big players, you’d expect that a report from a UK accident body would say the same as a European one, which in turn would say the same as a USA one.

And here’s the issue. Assuming that what I read is correct, there have been two reports from the AAIB and the NTSC about these cold flying issues on the 777, and while they broadly agree about the cause of the problem, they differ totally in the conclusions they draw about what to do in the meantime, and also in the way they choose to commit their words down on paper.

The USA NTSC’s conclusion in their letter to the EASA is stark and simple, and totally different from the AAIB’s view of the situation.

Therefore, until the current FOHEs (Fuel/Oil Heat Exchangers) are replaced by FOHEs more tolerant to ice accretion, additional failures to achieve commanded thrust could occur and could result in a serious accident and, possibly, injuries and deaths.

All of which, I an sure, is semantically accurate. But what a different message from the AAIB. One (the UK, and the home of the engine makers Rolls Royce) concludes that the issue (at least at the time they wrote their summary) had only happened once in 6,500,000 flying hours, and the level of danger to the passengers was therefore “remote”, and presumably acceptable. The other (the USA, and the home of the rival engine makers General Electric) ends with a conclusion which simply stops me in my tracks from flying on one.

I cannot believe that the two attitudes are accidental. The UK authorities shelter behind the EASA rules and definitions in deciding how to stake their position. Note they don’t say it’s safe, they just say that in terms of someone else’s categorisation of relative safety levels, it is "remote". The USA authorities come from a diametrically opposed position.

Both are “right”. But what is the poor sod getting on the aeroplane supposed to do now? Is the aircraft dangerous to fly in or isn’t it? I’ve lived long enough to realise that the difference between reality and perception is often enormous. I’ll guarantee that other aircraft suffer similar problems where safety is not the black and white issue we all think it is. It’s just that the customer doesn’t hear about it, either intentionally or unintentionally, and therefore gets on the beast in blissful ignorance.

In this particular case, even British Airways are compounding the problem. For reasons that only their labyrinthine financial wiz-kids could explain to me, they have a mixed fleet of Rolls and GE engined 777s. 15 are Rolls powered, and the remaining 27 are GE powered. BA, ever helpful, say that they will not tell passengers, even if they ask, what engines will be powering the 777 you are getting on. How on earth is that statement supposed to give the passenger any comfort? All it says to me is that there is clearly a problem, and a big one.

One can’t help but suspect that it’s all down to money. The 747 is a big, expensive aircraft to run, and in these disastrous times, passenger bookings have taken a tumble. So a smaller aircraft will do on many of the previous 747 routes. A website I’ve just looked at claims that 16 of BA’s 55 747s are “stored”. All the 777s are in use. What a surprise!

So BA are going to get maximum utilisation from their 42 777s, however they are powered. Their action just looks Machiavellian. If the issue goes away, the 42 777s keep flying and BA maximise their margins. If the pressure mounts, they will take the 15 out of service until the fix is available, and put as much pressure on Rolls Royce to get their act together NOW. But, in an industry where every operator tries to claim the high moral safety ground, how grubby does this look?

What happens if there is another “incident”? Perhaps one that turns out to be an “Accident”. One where people, lots of people lose their lives. Can you imagine the lawsuits that would follow now, especially in America?

I suspect that a lot of people in Rolls Royce are working all hours God sends to expedite a solution as quickly as they possibly can. A lot of people in Boeing, Rolls Royce, the National Safety Organisitions and BA will have every finger well and truly crossed while this is going on, hoping and praying that a third “incident” doesn’t happen. They will not sleep at all well until the time when all of their 15 777s are fitted with sets of modified Heat exchangers. Let’s hope they are right.

But you still wonder –

What would those reports look like if GE had the problem, and not Rolls Royce?

Does the NTSC report reflect their lawyers’ view of covering the corporate backside in the event of a disaster, or is it a non too subtle way of boosting GE’s position in the market place?

What will the AAIB’s bland position look like if one of these planes drops out of the sky?

Why can’t the Safety organisations get together and issue a set of reports which at least say the same thing, so the customer can feel that someone in this hugely complex industry is looking after their interests alone, even if it causes the airlines and the manufacturers some grief?

All I know is that, in the next few months, when I want to fly a long way, I will not be asking BA for a price for my next long haul flight. I’ll be going somewhere I know that doesn’t fly these things.

Stupid? I simply don’t know.

The truth is that, apart from looking back in a year’s time, I’ll never know if I’m doing something unnecessary or not. At least, however, the customer (that’s Me in this case) can make a choice here.

As a contrast to that, just ask the RAF Nimrod aircrews what they think about flying them for many months when it seems quite clear (to me at least) that there are fundamental and life threatening problems with that airframe. You can’t, of course, ask the 14 who died in a crash a while back for their opinion, but the UK Ministry of Defence has lost a massive amount of credibility by denying the existence of a problem that any clear thinking individual knows exists. What price the power of the Military?

Don’t the rules change when you’re in the Armed Forces.

1 comment:

Whitenoise said...

Nice summary, Roger. There are a few other variables- time of year, OAT (outside air temperature) and length of flight. If you're riding on a RR-powered triple across the equator to a sun destination- you're likely to be fine.

One other factor is type of jet fuel. Here in Canada we use JetA1 which has a lowest-useable temperature of -43C. In the US they use JetA with a lowest-useable temp of -36C. (These are limits in the tank, not the OAT. The fuel/oil heat exchangers and skin friction also have an effect.)

Interesting situation politically, none-the-less.