Just thought I would share some differences between the old 744 we have grown to love and the 747-800. These are not my words but from a 747-800 driver.

 

Part1.

 

The wing is different (supercritical) and the engines are more powerful and also a lot quieter. You don't feel the "kick in the pants" on the takeoff roll that you got in the 400, it just trundles along making very little noise and suddenly an electronic voice says "V1". Rotation is a more gentle affair since the beast is around 20 feet longer. The wing (?) makes the whole thing a bit more speed unstable on finals.

 

Under the skin there are a lot of differences. The outer aileron and spoilers are "fly by wire" and move around in flight to keep everything sweet. There are no flight deck indications of this. There is a RAT and the hydraulic system rearranges itself in the event of failures so that even on one or no engines, all control surfaces are powered. All the spoilers operate as roll augmentation and the elevator is split into 4 sections (2 each side). This makes the flight control check callouts slightly different. The ailerons also droop for takeoff and landing which improves performance. The CWT has a nitrogen system to prevent a repeat of the TWA incident.

 

On the flight deck, the ECS is made by Leibherr and pumps out a lot of air during certain flight phases. The noise can be quite startling at first. The gear lever is now just an up/down switch with no "OFF" position. The EICAS selector panel is off the 777 and can be used to display things all over the place.. An example is the ability to display the electronic checklist (another new toy) on the ND whilst the engine display is on the lower EICAS MFD. Oh yes, the screens are now called MFD's.

 

There is no clock, it is incorporated into the inner MFD and runs automatically from takeoff and the total flight time is displayed on the status page. The trim position is moved to the upper centre MFD and blanks after takeoff.

The FMC has several extra pages and has a display more like the 777. The whole thing is geared around RNP operations and there are three buttons on the glareshield to ACCEPT, REJECT or CANCEL ATC messages. The approach logic has been changed to something called Integrated Approach Navigation (IAN). What this means is that as long as an approach is in the FMC, all you have to do is select APPROACH and you are basically flying an ILS regardless of whether it is LNAV/VNAV, ILS, VOR or whatever. RNP scales appear on the PFD to show you where you are in relation to lateral and vertical profiles. Sounds complex but it makes life easier. There is a brand new radar which you basically leave in AUTO and it does everything for you. The ND features an airport map (not yet functional) and a vertical situation display which does clutter the ND a bit but I like it. You can switch it off.

 

The other new toy of note is the EFB. At the moment this is used to store manuals electronically and is used as a performance tool. The figures are very conservative, especially on landing as the brakes are the same for a heavier aircraft but these are being gradually tweaked by Boeing as experience is gained. The EFB also has a pilot utilities menu which contains a calculator and a conversion tool ( Litres to Kg etc). Eventually this gizmo will have charts and things.

 

On walk around, you will notice that the wheels are bigger, I can no longer fit between the body gear and gear door and it is not due to too many pies down route. Honest. You need to avoid the RAT doors in case it pings down and takes your head off. The whole thing is longer and takes more time to stagger around. The Nav lights are a bit different.

 

MTOW is 445 tonnes and MLW 345 tonnes for the freighter or thereabouts. The beast is longer and a lot better looking than the A380 and has a definite ramp presence. The only major whinge from our guys is the rearrangement of the galley which is now side on and gives less room to move about. There are more seats on the upper deck. Taxying needs you to go a bit deeper into the turns.

 

And thats about it. A nice bit of kit IMHO. The aircraft of choice for heavy lifting over long ranges. Fuel burn is about the same or slightly less than the 400 for a greater weight. We had 8tonnes/hour in the cruise the other night at around 385t. The 400 was a fairly constant 10t/hr.

 

 

Part2

 

The overhead panel has been tidied up a bit. The engine start panel is simplified, no more manual start or continuous ignition switches, the whole thing is automatic. The engines also monitor absolutely everything and shut themselves down if they don't like it. The 400 (CF6) only monitored Hot, Hung and no EGT rise.

 

The engines take longer to start than the CF6 (can't speak for the RR) and tend to vibrate due to rotor bow. They also produce quite a lot of smoke which alarms the ground crew. This is normal. The engines themselves look the dog's bo****ks with large scimitar bladed fan blades. So far they have been very reliable. Take off requires 40% to be set prior to pressing the blast off button. The ground anti ice procedure is a bit different and you need to watch vibration levels. Any more than 4 and you have to manually de ice the engines. Not been a problem so far, even in a frozen ORD. A PIP from GE is expected at some point to address some minor issues, including the smoky start.

 

There is no more Aft cargo heat switch, it is incorporated into the system elsewhere and the yaw dampers have to remain off until the IRS has aligned. The pack selectors have been replaced with simple PBI's.

 

That's all I can remember without looking at the manual and I'm on days off!

Nice to know, thanks for the info...

 

Rónán O Cadhain.

Imagine all this is included in pmdg's...

I went to watch the first of BA's - 8 Freighters arrive at Stansted, it was a maginificent sight. And you can't overemphasize how silent the -8's engines are. I live on the approach/departure path for Stansted, and Sunday just gone by one of the BA - 8's flew right over our house from take off, probably around 2000 ft at that stage, it is really quiet in comparison to the 400 freighters which go over here as well. A friend of mine who was onboard a BA - 8 for a South Africa flight told me that inside the cabin, the sound of the engines is almost inaudible. And I have to agree with the notion that the - 8 looks better than the A380. But I am probably biassed because of my huge affection for the 747.

You don't feel the "kick in the pants" on the takeoff roll that you got in the 400, it just trundles along making very little noise and suddenly an electronic voice says "V1".

 

I'd miss that - I LOOOOVVVVEEEEDDDDDDD the feeling of being pushed back in my seat by the 747-400 on take-off.

I never knew that there were that much differences between the 747-400 and the 747-8, I just knew that it's partial Fly-By-Wire and quiter and more fuel efficient, thanks posting this topic, I really wish I get the privilege to be at the controls of a 747-8 one day in the future

And I have to agree with the notion that the - 8 looks better than the A380. But I am probably biassed because of my huge affection for the 747.

 

Nope, you are not biased, the 747 is far more handsome than the A380. The A380 is undoubtedly a magnificent feat of engineering, but its looks are brutal rather than graceful. That's always the way with fully double-decked aircraft, they simply cannot appear slender, but the 747's partial double deck actually ends up accentuating its length, and that makes the main cabin look slender despite the fact that it is not.

 

Most of that's probably more by accident than intent, since the 747 was originally going to be fully double-decked if we look at some of the concept drawings, but they could not figure out a way to load/evacuate it within the required time with the technology of the late 60s, and the vast majority of airports were simply not geared towards handling aircraft of that size back then, which is in fact why the 747-100 puts out the same ground pressure footprint as a 707 amongst other things.

 

Al

Thank you for the very informative post Rob. Thank your friend. :)

Great information, I have this post stickier for future reference when the PMDG -800 is released!