air safety

Feb 21, 2013

Dreamliner ‘fix’: Will it restrict 787 ETOPS approvals?

Taking forward the US reports of the hour of a 787 fix to its battery

Ben Sandilands — Editor of Plane Talking

Ben Sandilands

Editor of Plane Talking

Taking forward the US reports of the hour of a 787 fix to its battery problems being formally offered to the FAA on Friday US time, what would its acceptance by the safety regulator do to the Dreamliner’s previous approval to fly a long way from emergency airfields while making oceanic or polar flights?

This would be a crucial question for all of the early customers hit by the January grounding, as JAL, ANA, United, Air-India and LOT Polish all want to fly the jet under so called ETOPS rules for up to 180 minutes single engine speed distance from such alternative landing sites.

But ETOPS approvals, which are required by all twin engined jets if they are to operate efficiently over oceans, deserts and frozen arctic wastes, are very strict about engine and electrical systems reliability, and even if the FAA allows the 787s back in air using an ‘interim’ fix to its battery problems, there are real concerns that discovering and permanently fixing the cause of the January battery crises on a JAL and ANA 787 will be a lengthy process.

While all modern twin engined jets are built to ETOPS standards, airlines can only use them if they have the approval of their national safety regulators and those approvals are conditional on such things as preventing the same maintenance team being responsible for both engines, so that any systemic mistakes aren’t made on both engines by the same engineers.

ETOPS 180, the industry standard, is theoretically needed even to fly as straight a path as possible across some parts of the Australian interior where jet fields are few and far between.

Boeing has long pushed the capability of the 787 to do ETOPS 330, that is, to be as far from an alternative field as it would take to reach it in 330 minutes on one engine, even though no airline is known to be using ETOPS 330 for any scheduled service today in any twin engined airliner.

The rules require a twin engined jet to land at the first available airport in the event of one engine failing or having to be idled. There are several motivations for this being a matter of urgency, unlike the case where an airliner has three or four engines.

One urgent reason is that if the cause of the first engine failure is going to affect the other engine, landing as soon as possible reduces the risks of that happening.

Another is that a twin engined jet flying on only one engine cannot sustain a high cruising altitude, and its forced descent to a sustainable altitude may infringe the safe minimum height rules over very high mountains, will adversely impact the fuel consumption of the remaining engine , and can result in the jet being at altitudes where its anti-icing system is called on to deliver maximum performance but with reduced bleed air or electrical systems capacity.

The complications are very well known and planned for by airlines using big twin engined jets, but the efficiency and reliability of such airliners as the 777 and A330 is such that emergencies like this are extremely rare, and mitigated by the strict ETOPS rules that apply to them.

But, those questions of engine and electrical system reliability will come back to the fore in the case of the 787, no matter whether an immediate temporary fix is approved, or when a permanent fix is devised and applied.

For Qantas which plans to use its first 787-8s under the Jetstar brand, ETOPS 180 is an essential prerequisite for efficient operations.

(Visited 1 times, 1 visits today)


Leave a comment

8 thoughts on “Dreamliner ‘fix’: Will it restrict 787 ETOPS approvals?

  1. bill mecorney

    Formally presenting a fix to the regulator prior to a report by the investigator?

    “We’ve got solutions, what’s your problem?”


  2. jeremyp

    I don’t understand what this has to do with ETOPS. Wouldn’t a four-engined 787, if such a thing existed, potentially have the same problems if it used the same battery technology? In general I don’t see how ETOPS rules can be construed to relate to systems on the airliner that are not connected the nature of having only two engines. If the batteries, or any other aspect of the electrical system, are fundamentally unsafe, they would be equally unsafe on four-engined planes on long segments, right? For example, the A340 doesn’t get away with any less regulation or safety standards on its electrical system as does the A330, right?

  3. Ben Sandilands


    Electrical systems reliability is critical to ETOPS reliability. To use a twin battery metaphor, appropriate to the 787, if one out of two major batteries fails, the risk of the other failing comes into play, not because of a risk to continued power supply to a type that makes unprecedented use of it (and perhaps in time, brilliantly) but because of the risk of that remaining battery being needed to kick start or overcome a more generalised electrical failure.

    The 787 is fine when everything is working. So is a 777 or an A330 or whatever. The problem is that if clearly something isn’t working reliably, or can’t demonstrate the incredibly high degree of reliability imposed by the ETOPS regimen, then the degree of approval is either downgraded or suspended, as indeed happened at times to 777 operators through no fault of their own when a fault was detected in some of the engines.

    Nothing is being ‘construed’ about the rules. We are dealing with the rules, and they are, of necessity, unforgiving, and indeed were made unforgiving by Boeing in its pioneering work on the adoption of ETOPS rules in the 1980s. (A different Boeing to the Boeing of today, by the way.)

  4. comet

    Boeing appears to have a hasty and careless attitude.

    It is eager to get longer ETOPS approval for the 787, when the radical nature and related problems of the aircraft demand some caution.

    It wants a quick and temporary battery “fix” before the real cause of the fires have been determined. It’s not really a fix, as it is really just adding basic safety precautions that should have been there in the first place with lithium batteries (eg greater spacing between cells, ceramic dividers etc), combined with fire containment (a thick titanium box with vent).

    If the Japanese leaks are correct, that the battery was wired incorrectly, then that doesn’t exactly solve the issue either. Planes are often delivered from the factory with incorrect wiring. Every time miswiring happens on a 787 is it going to erupt in flames?

    I feel uncomfortable with Boeing’s “get back in the air, no matter what” attitude.

  5. bill mecorney

    In an interview, John Goglia, (ex NTSB engineer) was blunt. Boeing had certified the Battery system to a threshold one one hundredth as demanding as the standard. How they did that is not public, but the threshold was a battery “event” only once in ten million flight hours. Boeing did not make it to one hundred thousand, and experienced TWO.

    It would not be out of order for FAA to require an additional ten million with no nonsense from either battery, THEN talk about ETOPS. That could happen only after Boeing fixed the problem, not just obtained a waiver to lift the grounding order, “in good faith…”

    Any “interim fix” will not have certification without extensive testing prior to carrying passengers. Perhaps even destructive testing, on an actual airframe.

  6. Achmad Osman

    As an interested neutral in all of this, my five cent piece is that Boeing should take a leaf out of the comet saga. When the first comet went down, DH and the Brit government should have grounded the planes – they did not and we know what happened afterwards.
    When the Brit government eventually grounded the planes and funded the testing to find the cause – the resultant Comet 4 was a vastly improved product flying up right until last year.

    The message is – ” do not rush the tests – do a proper job – it will be worth it in the long run”.

    To those that have an interest in aviation history – the DH engineers shared their work and the results of the comet tests and lessons in metalurgy rather naively with Boeing, allowing Boeing to build the B707 with all the incorporated DH knowledge and the rest is history.

  7. Theoddkiwi

    Could it be quite possible that the two battery issues are in fact completely unrelated? Its easy to say that because you have two problems that occur close together that they must be linked and be caused by the same thing. In my experience as a aviation professional, this is often not the case but has lead many a person down the wrong path. If one aircraft had a wiring defect that caused a problem and the other aircraft had a fault in the battery then that make things not look so dreary. ETOPS is important and reliability in the electrical system is a requirement. You should note in Australia ETOPS is now EDTO (Extended Diversion Time Operations) and applies to ALL long range aircraft regardless of numbers of engines as more then just engine reliability. Most diversions from EDTO/ETOPS are not in fact due to engine problems, Cargo Fire suppression ability being an obvious one. For the FAA ETOPS now stands for Extended Ops and like EDTO will/does apply to all long range operations regardless number of engines. If Boeing can prove their fix can withstand a battery failure for the appropriate ETOPS times which I am sure they would be considering they will have a case to allow ETOPS to remain, but maybe at reduced range.

  8. Ben Sandilands

    Good point about the standards that now apply. The difference operationally remains that in a big twin with a dead or idled engine, you must land at the first available strip. With a quad you can fly on to a more convenient airport.

    In the last few years at least one A380 over India en route to London experienced problems causing one engine to be idled, yet it continued all the way to London after re-filing for an intermediate city then diverting to London when it reached top of decent for that city, I think it might have been Warsaw, and was then able to change altitudes as per normal ATC requests and stay at FL360 or higher.

    In the case of a 777 they would have either landed immediately in India or Pakistan and FL360 would not have been possible nor would the remaining fuel load have sustained the jet for 12 hours single engine speed.

Share this article with a friend

Just fill out the fields below and we'll send your friend a link to this article along with a message from you.

Your details

Your friend's details