Early Boeing 747 Trivia
Hey Dan,
The B747 electrical system was designed by Westinghouse for the B707 in the 1950s. It had a few tweaks but for us ex B707 crews it was obviously a descendant of the B707.
The VC10 & VC15 had their own quirky electrics, replete with a mass of fuses. I didn't see too much similarity but I was only licensed as "Limited Class 2" for line maintenance on the Hush Puppy.
The B747 electrical system was designed by Westinghouse for the B707 in the 1950s. It had a few tweaks but for us ex B707 crews it was obviously a descendant of the B707.
The VC10 & VC15 had their own quirky electrics, replete with a mass of fuses. I didn't see too much similarity but I was only licensed as "Limited Class 2" for line maintenance on the Hush Puppy.
I flew the 747 after flying the VC10. When doing the 747 ground school course, I was mildly surprised that many of the 747 systems were remarkably similar to the VC10s. For example, the electric system was almost identical apart from which busbars were synchronised. Late, I found out that many of the design engineers who had worked on the VC10 had been employed by Boeing when work on the 10 finished, and they worked on Boeing's new project - the 747. So, rather than referring to the 747 as "The Queen of the Skies", it would be more accurate to refer to it as "The Princess". The daughter of the rightful Queen - the VC10!
Anyone who has flown both will probably agree with me.
Anyone who has flown both will probably agree with me.
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The reason they sit at LHR all day is the problem of the North/South route and only a one or two hour time change. European carriers mostly have no change of time zone and used to go out night and return day but as the Biz traffic increased, Biz did not want to waste a day and tourists neither. Consequently everyone pays for the 12 hours (or so) of parking time.
But most routes have some optimal times, based on connections at both ends. This is not just airline connections, but also surface ones. Arriving in the US notably late in the evening, and needing to allow for immigration/baggage collection delays, you may find your last onward travel has gone. It's a similar approach to that discussed for the daylight South Africa-Europe flights. If you arrive at Heathrow at 20.30 and want to go on to Dublin/Manchester/Edinburgh etc, let alone mainland Europe, your last flight will be unreliable or gone. Similar considerations for late arrivals in the USA, plus you will be jet-zonked feeling it's the middle of the night.
Even the much-vaunted O&D passengers will be trying to get home. I have got back to Heathrow at 21.30, and only just made the last Underground to my house, in London. Not everyone is getting a cab to a hotel. Even worse if you get to the hotel, or your house, at midnight, time zone-shifted, and tomorrow's meeting in the office starts at 08.00.
Nowadays (before lockdown that is) of course there are several flights across the ocean throughout the day; I remember Virgin Heathrow to JFK departing late morning to get to our hotel in Manhattan about 3pm and Heathrow to LAX departing early morning (about 9am) to land at about 3pm local.
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North/South routes in the Americas and the Far East such as SYD / NRT have the same problem as Europe to JNB + CPT. The charters and cheaper operators will turn immediately and return daylight but the main carriers will sit out the day waiting fo the biz pax.
How many of the 747 had the hard points for external loads , like the spare engine being ferried under wing ?
How many also had the drone option ? How many have both options ?
How many also had the drone option ? How many have both options ?
Gnome de PPRuNe
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Thanks Liffy, trust me to get it the wrong way round!
I remember seeing somebody's 747 coming off the Biggin stack with a spare donk inboard of No2, wasn't BA. Only time I recall seeing a spare being ferried.
Drone option?
I remember seeing somebody's 747 coming off the Biggin stack with a spare donk inboard of No2, wasn't BA. Only time I recall seeing a spare being ferried.
Drone option?
I lived through the B747 experience at Eastern Air Lines. I ran the Tech Service group at JFK. We leased from Pan American two aircraft for year around service and a third one for the winter when they were slack and we were peaking out. To cover the costs, EAL expected them to fly 14 hours a day. The aircraft were onl to fly JFK, MIA and SJU.
The early B747 were not easy to maintain. The Pratt JT9D-3 was a miserable engine early on and not great later on either. I remember UPS and Orion Air for whom I then worked celebrating as we replaced the last -3 with -model 7 engines on their then fleet.
Those early engines had no stall margin at all for a start. The aircraft was designed for long haul. A takeoff. eight hours of cruise and a landing. Our longest leg was three hours. The delay and cancellation rate was so bad that at one point my small Techie group s were assigned to ride jumpseat on every flight for three days and report on what was doing wrong. Not acceptable was that it was the aircraft and engines that were still raw and for the time, were cutting edge and not matured. Nothing of course came of that except exhaustiuon on our part.
Then the VP of Line Maintenance, under the gun himself, announced that he would come up to JFK and ride with me around the ramp and HE would see what we were doing wrong.
JFK overnighted one aircraft but on this day it was coming out of a Pan Am maintenance check. The APU on the aircraft had been inop for a week and had been declared a failure by one of my Techies due to compressor rub. VP and I sat in my Econoline to the side of the aircraft and the VP was acrid pointing out the shiimer from the APU tailpipe and reminding me that PA AM had fixed it by just changing the battery.
The stairs came offn. Tug began the pushback, the APU tone changed as they started winding up Nbr 3 engine when the was a loud bang, flames and a few hard parts out the APU tailpipe. I couldn't gloat, not to a VP but I did mention that the battery change had not fixed it.
Aircraft pulled back in, APU inspected, put on MEL and two huffers and grouynd power needed to start nbr 3. Tug pushed back , then stopped once again and pulled back in. Up went the stairs, up went me with electrician. Front cabin stunk of electronic smoke. A passenge entertainment MUX controller had cooked off. Pax entertainment went on MEL too and I happily carried unit, still stinking back to my Econoline for VP perusal. A/C finally departed.
In came Miami flight. On gate a mechanic motioned me over to nbr 2 engine. A bleed air outlet opened on the side of the cowling with a coarse screen coverong it. A 2" x 2" flat piece of metal was caught up in it. I knew it was a piece of the inner case and pulled the a/c out of service for an engine change. Informed VP that I had seen this before.
Third a/c arrived from SJU. On taxi in I could see nbr 3 cold stream reverser was stiull partially deployed and there seemed to be material sticking out of the gap. Yes indeed, the engine had a hard stall on reversal and some acoutic liner had come loose. Second engine change required today. Also Nbr 4 engine had the hot stream reverser partially deployed too. It had jammed causing the reverser actuator on the gearbox to come apart. Ball bearing and bits insode the cowling.
The VP got on the next Miami flight. His only statement was on asking how I had arranged all this to happen. I told him it was not an uncommon day.
Apologize for being wordy.
The early B747 were not easy to maintain. The Pratt JT9D-3 was a miserable engine early on and not great later on either. I remember UPS and Orion Air for whom I then worked celebrating as we replaced the last -3 with -model 7 engines on their then fleet.
Those early engines had no stall margin at all for a start. The aircraft was designed for long haul. A takeoff. eight hours of cruise and a landing. Our longest leg was three hours. The delay and cancellation rate was so bad that at one point my small Techie group s were assigned to ride jumpseat on every flight for three days and report on what was doing wrong. Not acceptable was that it was the aircraft and engines that were still raw and for the time, were cutting edge and not matured. Nothing of course came of that except exhaustiuon on our part.
Then the VP of Line Maintenance, under the gun himself, announced that he would come up to JFK and ride with me around the ramp and HE would see what we were doing wrong.
JFK overnighted one aircraft but on this day it was coming out of a Pan Am maintenance check. The APU on the aircraft had been inop for a week and had been declared a failure by one of my Techies due to compressor rub. VP and I sat in my Econoline to the side of the aircraft and the VP was acrid pointing out the shiimer from the APU tailpipe and reminding me that PA AM had fixed it by just changing the battery.
The stairs came offn. Tug began the pushback, the APU tone changed as they started winding up Nbr 3 engine when the was a loud bang, flames and a few hard parts out the APU tailpipe. I couldn't gloat, not to a VP but I did mention that the battery change had not fixed it.
Aircraft pulled back in, APU inspected, put on MEL and two huffers and grouynd power needed to start nbr 3. Tug pushed back , then stopped once again and pulled back in. Up went the stairs, up went me with electrician. Front cabin stunk of electronic smoke. A passenge entertainment MUX controller had cooked off. Pax entertainment went on MEL too and I happily carried unit, still stinking back to my Econoline for VP perusal. A/C finally departed.
In came Miami flight. On gate a mechanic motioned me over to nbr 2 engine. A bleed air outlet opened on the side of the cowling with a coarse screen coverong it. A 2" x 2" flat piece of metal was caught up in it. I knew it was a piece of the inner case and pulled the a/c out of service for an engine change. Informed VP that I had seen this before.
Third a/c arrived from SJU. On taxi in I could see nbr 3 cold stream reverser was stiull partially deployed and there seemed to be material sticking out of the gap. Yes indeed, the engine had a hard stall on reversal and some acoutic liner had come loose. Second engine change required today. Also Nbr 4 engine had the hot stream reverser partially deployed too. It had jammed causing the reverser actuator on the gearbox to come apart. Ball bearing and bits insode the cowling.
The VP got on the next Miami flight. His only statement was on asking how I had arranged all this to happen. I told him it was not an uncommon day.
Apologize for being wordy.
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SAA early 747s
Early SAA 747 flights were required to route around the continent's western bulge, adding significant mileage.
This lead to heavy fuel loads & P&W allowed SAA to use ‘redefined thrust’ for takeoff. SAA had a world class jet engine shop that facilitated the higher thrust’s required maintenance specs.
This lead to heavy fuel loads & P&W allowed SAA to use ‘redefined thrust’ for takeoff. SAA had a world class jet engine shop that facilitated the higher thrust’s required maintenance specs.
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I flew the 747 after flying the VC10. When doing the 747 ground school course, I was mildly surprised that many of the 747 systems were remarkably similar to the VC10s. For example, the electric system was almost identical apart from which busbars were synchronised. Late, I found out that many of the design engineers who had worked on the VC10 had been employed by Boeing when work on the 10 finished, and they worked on Boeing's new project - the 747. So, rather than referring to the 747 as "The Queen of the Skies", it would be more accurate to refer to it as "The Princess". The daughter of the rightful Queen - the VC10!
Anyone who has flown both will probably agree with me.
Anyone who has flown both will probably agree with me.
Paxing All Over The World
The heavily western route for SAA was why they were prime candidates for the SP version. Over many years, Ilha da Sal in the Cape Verde islands was their splash and dash + crew change for many years. When the extended range versions became available, the island lost a lot of good custom! Wikipedia gives details of the SAA routes Amílcar Cabral International Airport has the IATA code SID, which has led to problems for some pax in the past!
On the way to Mauritius (BA; stopped at Nairobi and Seychelles outbound and on the return, Rome too) , we stopped at Nairobi and when it came to departure one engine wouldn't start so they stuck us in a hotel and ferried another engine in from South Africa and next time we tried departing we had the dead spare hanging on to us.
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Fifth pod between #2 and the fuselage was the main way to ferry a spare engine. For a time my company was overhauling engines for a Chinese operator. We fifth podded regularly between Sydney, Beijing and back.
On one occasion we carried an engine for a Flying Tiger 747 100 which was a slightly smaller diameter. It was a Sunday afternoon and we were transiting Melbourne. When we moved the engine dolly in it couldn't raise enough for the early series engine so we let the aircraft tires down. Was a good idea until we discovered that there was no nitrogen available until Monday
As far as similarity of the electrical system to the B707, the 747 was so similar for most systems including electrical that when we converted to the 747 from the 707 we didn't do a type course, only a differences course.I seem to remember that the VC10 electrics were a bit similar but quite a few differences.
In an earlier life I was licensed Elec and Instruments of the B707. From what I remember of the VC10, it wasn't that close to the B707
On one occasion we carried an engine for a Flying Tiger 747 100 which was a slightly smaller diameter. It was a Sunday afternoon and we were transiting Melbourne. When we moved the engine dolly in it couldn't raise enough for the early series engine so we let the aircraft tires down. Was a good idea until we discovered that there was no nitrogen available until Monday
As far as similarity of the electrical system to the B707, the 747 was so similar for most systems including electrical that when we converted to the 747 from the 707 we didn't do a type course, only a differences course.I seem to remember that the VC10 electrics were a bit similar but quite a few differences.
In an earlier life I was licensed Elec and Instruments of the B707. From what I remember of the VC10, it wasn't that close to the B707
AFAIK, that's the only "external load" that can be carried - the drop tank option didn't find favour with any customers.
I flew out of Los Angeles in July 1990 in a very full 747-211B , G-GLYN. The take off roll seemed very protracted but we got away OK and had a reasonable flight back to Gatwick. Although it was a BA flight, the aircraft had been owned by BCal and had spent some time in the desert being stored between ownerships. Talking to an ex BCal captain (Mike Graty anybody?) he claimed that when it was "opened up" for a major service BA found a noticeable amount of "Mojave" sand in it which helped explain the poor fuel consumption and takeoff performance..Not sure how true this was but BA didn't keep it very long.