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-   -   Goodbye BA Jumbos (https://www.pprune.org/aviation-history-nostalgia/634106-goodbye-ba-jumbos.html)

tdracer 25th Jul 2020 21:07


Originally Posted by treadigraph (Post 10846234)
I seem to recall damaged winglets have occasionally been removed before a revenue flight and the aircraft flown home?

The winglets were on the MEL/CDL/DDG - dispatch was allowed for (I think) 10 days - I don't recall if it was for one or both missing... The short range -400 didn't get winglets (IIRC JAL did something where they used 747-400s for short range service until they got up to a certain number of cycles, then converted them to long range aircraft to get the hours out of the airframe - rather clever).


Originally Posted by treadigraph (Post 10846234)
Why did the production 747-400 and 800 freighters not have the stretched upper deck? Keep airframe weight down a bit to improve loads carried on the main deck?

Yes, I believe it was airframe weight - they couldn't use the additional space and the extra airframe weight meant less cargo. Also, the cargo operators are less concerned about cruise speed - apparently cruising around at 0.80 to 0.82 is pretty common for a 747F while passenger aircraft seldom go that slow - and the area ruling benefit comes into play at about 0.84.

treadigraph 25th Jul 2020 21:26

Cheers! Occasionally wondered about the freighters...

Meikleour 26th Jul 2020 09:25

tdracer: Do you have any knowledge of the "pod nod" applied to the R-R engined B747-2/300? I was told that although the airframe was optimised for M.86 cruise it was more commomly cruised slightly slower with a commensurate higher cruise pitch attitude. The "pod- nod" applied a slight droop to the pods giving a better alignment for the slower cruise speed and hence a slight fuel burn improvement.

wub 26th Jul 2020 14:45

https://cimg9.ibsrv.net/gimg/pprune....577503acc6.jpg
My favourite cabin in the sky
https://cimg4.ibsrv.net/gimg/pprune....cb5f006a8d.jpg
Taken from the window in the rearmost door. I'll always remember this because unknown to me, a lady was standing behind me waiting for a look and as I stood up to leave I smacked her nose hard with the back of my head.
https://cimg3.ibsrv.net/gimg/pprune....7e7a75c7a1.jpg
My last BA 747 trip in 2015, thereafter the routes I fly were operated by A380s and 777s

vctenderness 26th Jul 2020 16:28

Pre 9/11 I carried Paul McCartney on a 747-400. I told the captain he was on board and he asked me to invite him to the FD.

I took him up the stairs and on reaching the top he exclaimed “wow this is really nice it’s like a private jet”. I realised that, of course, he had only ever flown in First Class in the nose and had never seen the lovely Club Upper Deck!

I had to persuade him he was better off spending his dosh on First Class travel.

srjumbo747 26th Jul 2020 17:52


Originally Posted by tdracer (Post 10846247)
The winglets were on the MEL/CDL/DDG - dispatch was allowed for (I think) 10 days - I don't recall if it was for one or both missing... The short range -400 didn't get winglets (IIRC JAL did something where they used 747-400s for short range service until they got up to a certain number of cycles, then converted them to long range aircraft to get the hours out of the airframe - rather clever).


Yes, I believe it was airframe weight - they couldn't use the additional space and the extra airframe weight meant less cargo. Also, the cargo operators are less concerned about cruise speed - apparently cruising around at 0.80 to 0.82 is pretty common for a 747F while passenger aircraft seldom go that slow - and the area ruling benefit comes into play at about 0.84.

The MEL stated that you could fly with one off but not both! Go figure!!!
Also, getting the winglet off was a difficult task and if you were down route when it happened you had to watch the duty hours.

tdracer 26th Jul 2020 19:57


Originally Posted by Meikleour (Post 10846530)
tdracer: Do you have any knowledge of the "pod nod" applied to the R-R engined B747-2/300? I was told that although the airframe was optimised for M.86 cruise it was more commomly cruised slightly slower with a commensurate higher cruise pitch attitude. The "pod- nod" applied a slight droop to the pods giving a better alignment for the slower cruise speed and hence a slight fuel burn improvement.

No, sorry. I didn't start working the 747 until the mid 1980's. We did some work on inlet droop on the Pratt powered 767 in the mid 80's but it never amounted to anything.
The only 'pod nod' I'm familiar with was actually "pod nodding" - also known as "orbiting engine". There was an instability in the fuel control of the early CF6-80C2 engines that could couple with the natural frequency of the strut and cause the inlet to move in a little orbit that could be seen and felt from the cabin - rather disturbing but fortunately it turned out to be an easy fix...

Fris B. Fairing 26th Jul 2020 22:53


The MEL stated that you could fly with one off but not both! Go figure!!!
There was speculation that it might be related to the nav lights but these are not on the winglet. An alternative explanation was that Boeing never anticipated a requirement to remove both winglets so they never tested it and therefore it was never incorporated in the manuals.

gas path 28th Jul 2020 17:12


Originally Posted by Cornish Jack (Post 10841770)
The flight deck size was most noticeable when I was moved from Tristar to 400 tech training. The Tri was ENORMOUS! ... the 400, cosy! ...the Concorde? more akin to an MG TC!
One passing thought - what will happen to the blue disc on the outside of Cranebank main building - future users will wonder why it's there. (installed to indicate the height of the 747 'fin' top)

There's two discs on that wall! I remember being told the lower one was the flt deck height when on the ground. The upper one (very faded) was the height above the concrete after main wheel touch down.

DaveReidUK 28th Jul 2020 17:38


Originally Posted by gas path (Post 10848240)
There's two discs on that wall! I remember being told the lower one was the flt deck height when on the ground. The upper one (very faded) was the height above the concrete after main wheel touch down.

See discussion earlier in the thread about the relative heights of the discs, and the 747 geometry.

gas path 28th Jul 2020 18:01


Originally Posted by Meikleour (Post 10846530)
tdracer: Do you have any knowledge of the "pod nod" applied to the R-R engined B747-2/300? I was told that although the airframe was optimised for M.86 cruise it was more commomly cruised slightly slower with a commensurate higher cruise pitch attitude. The "pod- nod" applied a slight droop to the pods giving a better alignment for the slower cruise speed and hence a slight fuel burn improvement.

The last of BA's -200's BDXP had different (basically -400) pylons, they had a noticeable droop to them ( 5deg?? IIRC), That was there as stated to improve airflow into the engine especially during rotation. There was one other of the fleet and the reg. I cant remember had a no.4 pylon only to the same standard as we replaced it due to overheat damage.

Self loading bear 28th Jul 2020 19:15


Originally Posted by DaveReidUK (Post 10843267)
Here are the marks in question on the Block C offices at Cranebank:


https://cimg9.ibsrv.net/gimg/pprune....d0db28396b.jpg

The legend on the photo does indeed suggest that the both discs relate to pilot's eye height.

That said, a quick back-of-the envelope calculation would suggest that the greatest eye-to-wheel height achievable in the flare on a 747, just short of striking the tail, would be about 15 m, compared with the aforementioned 9 m eye-to-wheel height when taxying. But the upper disc in the photo looks to be at least twice as high above ground level as the lower one, although the parallax makes it hard to be sure (any photogrammetry experts out there?).

I believe the building in question may have now gone, so it looks like we might never get a definitive answer. :O

https://www.reddit.com/r/flying/comm...eight/cuphyl3/

Photgrammatery is not required. Counting building levels will do.
from Boeing 747-800:
eye height cockpit 8,71m (lowest plate looks corresponding at 2.5 floors)
A flare of 10 deg and 34m distance between main gear and cockpit adds 6m (so indeed not doubling the height)
tail height 19.6m (highest plate look corresponding with 5+2/3 Floors)

rog747 30th Jul 2020 14:52

BA 747 enthusiasts farewell flights
 
BA have replied to us stating they have no interest in organising any 747 farewell flights - sorry folks

my thanks for assistance to pal David Skillicorn
(Previous MD of Bath Travel/Palmair Holidays)
Cant say we didn't try....We were looking to work maybe 3 or 4 rotations, retro a/c if poss, - Def would have sold out & filled them all up.
Hey ho...

GS-Alpha 30th Jul 2020 16:15


Originally Posted by rog747 (Post 10849628)
BA have replied to us stating they have no interest in organising any 747 farewell flights - sorry folks

my thanks for assistance to pal David Skillicorn
(Previous MD of Bath Travel/Palmair Holidays)
Cant say we didn't try....We were looking to work maybe 3 or 4 rotations, retro a/c if poss, - Def would have sold out & filled them all up.
Hey ho...

Sadly they have got far more pressing matters to be dealing with, than worrying about putting on a couple of farewell commercial flights for the 747. It is tantamount to asking a bus driver to take you just a couple more miles up the road, whilst he/she is slumped at the wheel having a heart attack.

Fareastdriver 30th Jul 2020 19:13

Should you not be able to fly in a British Airways 747 there are plenty of other airlines.

https://en.wikipedia.org/wiki/List_o..._747_operators

tdracer 30th Jul 2020 20:39


Originally Posted by Fareastdriver (Post 10849777)
Should you not be able to fly in a British Airways 747 there are plenty of other airlines.

https://en.wikipedia.org/wiki/List_o..._747_operators

Lufthansa, Korean, and China Air bought significant numbers of 747-8 passenger aircraft.
At least Lufthansa has indicated they intend to keep their 747-8s in service once traffic returns past pandemic.

ExSp33db1rd 31st Jul 2020 00:38


One of my old mates when asked why he had always flown four engine aircraft, replied, "Because no one has built one with five engines."
Was once told that no airline Captain would be satisfied until the F/Eng. could say " We've lost No 8, Sir ( never forgetting the Sir ! ) " and the Captain could reply, " Which side ? "


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