Boeing 747-8F

Awww. Now we have to think of another witty replacement for “Engines Turn Or Passengers Swim”… 😀

Long story short, ETOPS is switching to EDTO (Extended Diversion Time Operations) which will apply to 3 and 4 (don’t know about 6 and 8?!) engine aircraft.

Amiga, I would enjoy hearing the specifics of the two areas you mention.

Airbus don’t route electrical cabling through their fuel tanks. A pretty critical difference when it came to the centre fuel tanks exploding. Yet the FAA/EASA fuel tank flammability exposure rule applies/applied to both Airbus and Boeing (as well as Bombardier, Embraer etc).

The Airbus cargo bays don’t circulate air to the aircraft bilge; leakage is reduced markedly, meaning cargo fire suppression is somewhat easier.

I’ve always thought that Airbus tepid support of Extended Twin Engine Operations was due to wanting to protect their investment in the 340 and 380, and also due to some of their prime customers not exactly embracing it either. Lufthansa comes to mind.

I agree on A340 – but not on A380; it was started well after the 777 and to a lesser degree the A330 showed the potential of ETOPS aircraft. Don’t forget that Airbus’ future projects bunch would have been looking at A350* in the ~2000-2005 timeframe (if not earlier).

*which looking back, and considering NEO, was probably the right approach – they should have ignored the airlines – they are like little children wanting the newest toy rather than the most suitable solution.

Amiga, I would enjoy hearing the specifics of the two areas you mention.

I’ve always thought that Airbus tepid support of Extended Twin Engine Operations was due to wanting to protect their investment in the 340 and 380, and also due to some of their prime customers not exactly embracing it either. Lufthansa comes to mind.

agincourt, i don’t have much knowledge of the rules for freighters. i would suggest going to a search engine and typing “far 121.161” and then start looking at the regulations after that one. Of course, these are U.S. regs, carriers from other countries wouldn’t necessarily need to observe them, but as a U.S. producer Boeing is building their aircraft to comply with U.S. regs.

Boeing supported the new regs, Airbus was not obstructive, but their level of support was certainly tepid.

That might be due to different design philosophies between the two.

I can name two areas, connected but separate at the same time, which Boeing’s design philosophy differs markedly from Airbus, with corresponding sensitivities to regulations… or maybe a better way of putting it would be ‘with correspondingly different regulatory needs’. That may sound like BS, but given the design differences, does make sense.

I would imagine there are many more I don’t know of.

From Wikipedia, for what it’s worth, current regulation states:

“all-cargo operations in airplanes with more than two engines of both part 121 and part 135 are exempted from the majority of this rule.”

From Flight Blogger August 2nd

“Boeing pointed out the max endurance flight is being flown under F&R certification, not ETOPS. As it turns out cargo models are exempt from the ETOPS rules as part of the 2007 update.”

Can anyone clarify?

I seem to remember that all the early engines burped a small amount of fuel when they shut down. As a mechanic, if you were doing engine runs/trimming, you didn’t want to be under the drain mast when the engine shut down or you would get a few ounces of fuel on you. The last 20-30 years or so, the engine manufacturers have developed a system to catch that fuel, or modified the engine so it doesn’t do that little squirt.

With regard to ETOPS for the 747, yes ETOPS applies. The FAA changed the regulations in 2008. One of the changes what the definition of ETOPS from Extended Twin Engine Operations to Extended Operations. The intent was to standardize the regs. Prior to the new regs you had scenarios where, for example, a 4 engine airplane might be 3 hours from an airport but only had 2 hours of fire suppression in the bag bins because 4 engine airplanes were “safer.” The industry finally realized that if you are on fire or out of fuel, it doesn’t matter how many engines you have. A lot of other regs that came into being at the same time “legitimized” Extended Twin Engine Operations, which until that time had operated under an Advisory Circular. Boeing supported the new regs, Airbus was not obstructive, but their level of support was certainly tepid.

I thought I read that the GE Engines vent small quantities of fuel overboard when the engine is shutting down? Did they not say that it saved more fuel during the shutdown doing it this way?

Edit – Must have imagined it, can’t find any reference to it.

B747-8F doesn’t need ETOPS but the long flights were part of the F&R (Function and Reliability) requirements. BOE522 was doing the final certification requirements for the Honeywell management computer (FMC) checks.

It’s all systems go for final FAA certification, likely coming in the next month and then delivery of the first aircraft to Cargolux.

FAA orders GE to modify engines for 787, 747-8

Article excerpt from the Seattle Times

FAA orders GE to modify engines for 787, 747-8

The Federal Aviation Adminstration (FAA) is requiring GE to modify its jet engines for Boeing’s two new airplanes, the 787 Dreamliner and 747-8 jumbo jet, because flight tests have revealed releases of small amounts of fuel into the air after the engines are shut down.

GE has been given more than a year to comply, so the Boeing jet programs won’t be delayed by the requirement.

“Small quantities of fuel (up to 5.5 ounces) are being released intermittently under certain conditions,” stated an FAA filing made Tuesday concerning a decision dated July 14. “Under certain atmospheric conditions this release of fuel results in a visible vapor.”

The inadvertent releases from the GEnx engines are caused by unexpectedly high pressures inside tubes that distribute the fuel.

Source: http://seattletimes.nwsource.com/html/businesstechnology/2015736608_geengines27.html

This may sounds stupid, but why is the four engined 747 doing ETOPS?

It looks like it flew over my ranch.

Here is the picture: http://boeingblogs.com/randy/archives/2011/08/747.html

Also, the 747-8F has certification flight test campaign. I take it is now just the FAA paperwork left to complete.