Last month, I talked about how the British Airways 777 accident and the Delta 777 incident had been connected by an interim report from the UK. The NTSB has, after review, agreed with these findings and is now requiring “urgent” action. But “urgent” is not as dire as it sounds. It does not require aircraft to be grounded, and it will take at least a year, most likely, before the work is complete.
The NTSB has told Rolls-Royce that it needs to redesign the Fuel Oil Heat Exchanger (where cold fuel passes hot oil and they cool/warm each other to proper temperatures) to prevent ice 
accumulation and subsequent blockage of the the fuel lines. You may remember that the hot oil wasn’t properly warming the cold fuel and ice was forming. This has, so far, only been a problem on the Rolls-Royce Trent 800 engines, though Rolls believes that this could ultimately have a larger impact after further research is done on icing for long flights at very cold temperatures. But that’s another story.
Rolls is working on the fix already and expects to have it ready within a year. Once the redesign is complete, airlines will have no more than six months to implement the fix. So if this is so “urgent,” why aren’t the planes being grounded? Well, procedures have already been put into place to help avoid these types of incidents, but the NTSB doesn’t think that’s a good long term solution. In the NTSB’s words:
While the procedures may reduce the risk of a rollback in one or both engines due to [Fuel Oil Heat Exchanger] ice blockage, they add complexity to flight crew operations, and the level of risk reduction is not well established. And because the recovery procedure requires a descent, the aircraft may be exposed to other risks such as rising terrain or hazardous weather, or the inability to achieve maximum thrust during a critical phase of flight, such as during a missed approach.
So while the fix they’re using right now does work, it’s not satisfactory in the long term. So should we worry about stepping on a Rolls-Royce powered 777? I wouldn’t. But it is clear that there are problems and it’s good to see them being addressed sooner rather than later.
17 comments on “NTSB Tells Rolls-Royce to Redesign 777 Engine Parts”
Your graphics are always awesome and this one (the ice cube on the wing) takes the cake. I know this is a serious topic, but good monday morning chuckles here! Thanks!
18 months is a long time, and should set one thinking. However, we should balance this with the fact that there have been two incidents against a fleet of about 220 B777s powered by Trent 800s worldwide that have been flying for quite some time.
I have written to elicit responses from Singapore Airlines, the world’s largest B777 operator. Hopefully will have an article in the next two days.
It’s good to hear that these issues are being dealt with swiftly, although there is still something disconcerting about this.
I buy the notion that a year-18 months is probably the soonest that the upgrades can be implemented due to the R&D and production/hangar time needed to make these changes. Nonetheless, 2 of 250 Trent 800-powered 777s comes out to just shy of 1% of the fleet that has already experienced serious incidents related to this issue (one of which, as everyone knows, resulted in a hull loss). Obviously, the actual percentage of flights affected is miniscule-negligible, but 1% of aircraft actually seems fairly significant.
At the end of the day, it would be economically impractical to ground 250 777s for a year, especially given the fact that stopgap measures have been identified. Still, are they not taking a bit of a calculated safety risk here? I say this understanding the fiscal and logistical realities of the situation. You simply cannot ground those many planes for that long, especially given the low issue frequency.
I’ll be stepping on a Trent 800-powered BA 777 without hesitation in a couple of months, so I’m in no way suggesting that people should be afraid to fly these aircraft. I’m simply wondering if this is a textbook case of the economic realities of the industry butting heads with safety considerations.
Zach – One thing we have to keep in mind is that it seems to be an issue with the engines and not the aircraft itself (so far). So if that’s the case, then it’s really a far smaller percentage of total 777 engines.
Where it gets a little dicier is that this is only on long haul flights with long flight times at very cold temps. And it seems that this isn’t cold temps you find on Transatlantic flights from the east coast but rather the polar routes that spend a lot of time in VERY cold weather. So on those flights, this becomes much more likely, though still highly unlikely. Now that they have these interim measures in place, that should reduce the likelihood even further, and that has to be why they aren’t grounding the planes. It’s really such a long shot and we know everyone will be paying very close attention, so it’s ok as a very temporary measure.
Or so I assume.
Zach and CF,
SQ – which I think is the world’s largest operator of 777s – made it clear that their 777 that have the Rolls Royce engines are not flying long-haul polar, and thus they will continue to operate it. The link to the FT site, where someone posted the article, is here.
http://www.flyertalk.com/forum/cathay-pacific-asia-miles/932690-777-rolls-royce-engines.html
The other concern I could think of would be CX, but CX’s 777-300ERs (which they fly HKG-JFK and previously HKG-YYZ, both which go over the pole a lot of the time) are all powered by GEs I think so there’s not a problem.
Any definitive list of airlines that operate 777s with Trent 800 engines? Thanks in advance!
Air New Zealand operate eight 777’s with Rolls Royce Trent 800’s. They also use them heavily on the LHR-LAX route, which exposes them to the very low temperatures of greatest concern. The airline has issued the standard press release about compliance and new procedures. However, the general public are not aware of the unique nature of this problem. It would seem that airlines like AirNZ could greatly reduce the risk by replacing the 777 with the 747 on the vulnerable route, at least until Rolls Royce have resolved the issue and new parts are fitted.
A definitive list of 777’s with Trent 800’s flying vulnerable routes would be most useful and then comment from each airline concerned about their approach to the use of the 777 on those routes…This is citizen journalism at its best and as the quote at the top of CF says…”There’s nowhere for them to hide”…
QRC – Thanks for sharing that link. The only aircraft affected are the 777-200/-200ER and the 777-300 (non-ER) aircraft. The 777-300ER and 777-200LR aircraft are exclusively powered by GE engines. Non-ER 777-300s are pretty rare.
RL/Peter Harris – Here is the full list of airlines operating Rolls-powered 777s to the best of my knowledge. Remember, if you’re on a 777-300ER on one of these airlines (like Cathay) or a 777-200LR (like Delta), those will be GE-powered.
British Airways (mix of Rolls and GE)
Air New Zealand
American
Cathay
Delta
Singapore
Emirates
Thai
Malaysia
El Al
Kenya
Finally! Tnx God we have NTSB report asking some action to be taken..
I do agree we have a fairly small percentage of loss and also there are conditions to meet to make a plane vulnerable..
Can somebody explain me what temperatures are reached over the Polar? i see on the screens while flying non polar routes easily -50/-60’C, so i wonder what that would be..
Anyway, i found odd BBC and other media going public with this news: ppl don;t have insight knowledge.. anyway, not a big deal, people easily forget too.. if less people is flying now is only due to economic downturn.. altough, as some airlines are cutting capacity.. they could think about cutting these models… i know i know, depends on the routes they fly.. was just a suggestion!
I’m sure that Rolls Royce, Boeing and each of the airlines operating the 777/Trent 800 combination must be dealing with some very serious insurance issues this week. The NTSB report makes it clear that preventative procedures may not be effective to avert the risk and that the only solution is a re-designed engine part.
Given such a public statement, if there was to now be a significant crash caused by the failure of Trent 800 engines on a 777, can you imagine the claims that would be filed against Rolls Royce, Boeing and the airline for continuing to operate an unsafe aircraft, in the face of such a warning?
My guess is that the litigation would be great enough to potentially take down Rolls Royce and possibly even a major airline.
I’m sure this fact has not escaped their insurers.
Flying Blue – You can read my first post on the accident for specifics on temperature. I highly recommend reading the report I link to. But some of the specifics involved the very cold takeoff fuel temperature that was below 28 F. At one point, the fuel temp went below -8 F.
Peter Harris – I think you’re probably very right on this one. Of course, grounding the entire fleet might be enough to bankrupt Rolls as well (probably not Boeing). You hate to think about this way, but you know that someone has done the probability chart on how to best proceed.
CF – Good point. Perhaps one of the reasons they did not ground the fleet is that it could have brought down Rolls Royce, which would not have made the development of the new component any easier!
What a thought that someone in an Insurance office this week has calculated the increased risk of continuing to operate the 777/Trent 800 aircraft in the face of the NTSB release and the chance of another accident and then determined the cost of that risk to the airlines involved! ….I guess its just the value of the lives of 300 passengers x the responsibility for operating with a known fault x the likely litigation…..? maybe all those AIG executives need their bonuses after all!
Finally got the answers from Singapore Airlines and their confidence in the Rolls Royce Trent 800 engines. http://www.bangaloreaviation.com/2009/03/worlds-largest-boeing-777-operator.html.
Devesh – Great stuff. Thanks for sharing.
“Rolls is working on the fix already and expects to have it ready within a year. Once the redesign is complete, airlines will have no more than six months to implement the fix.”
Hard to believe it was urgent, but that more was not being done about it. Good to hear they are working on a fix. It has been long enough that surely that is taken care of now.
Hey CF,
Do you have an update on this? How are supposed to be the new engines with the fix?
I don’t have an update, but I would assume that everything is fine now.