Posts by user "Shaggy Sheep Driver" [Posts: 67 Total up-votes: 0 Page: 1 of 4]¶

Wow, what a great thread! I started reading it yesterday and am up to page 19 so far! I flew on the wonderful white bird once, in 1999, a Manchester - round the bay at Mach 2 - Paris flight in G-BOAD. And the wonderful thing was I did the entire flight, push back at Manchester to parking at Paris, in the jump seat! What a fabulous experience - thank you Roger!

Here's a picture I took as the aircraft turne left towards the French coast:



One memory is climbing through 50,000 feet over South Wales before turning down the Bristol Channel. It was glorious August day and I had a great view forward past the captain and particularly out of the left window. The speed over the ground at Mach 0.95 seemed noticably faster than a subsonic jet, and that view was breathtaking! The Bristol Channel was edged in golden yellow beaches, and I could see right across south west England to the English Channel. In my headset the controller called another aircraft; "Speedbird 123 if you look up now you will see you are about to be overflown by Concorde". I leaned towards my side window and there was Speedbird 123, a tiny scurrying beetle miles below us. From this height the fair-weather cu looked as if they were on the ground - like small white splodges from some celestial artist's paint brush.

We cruised at Mach 2 and 60,000' over the Bay for a while and the pax came forward to view the flightdeck. I was amazed how patient was the supernumery captain who was answering the same questions over and over again was (the flight crew were too busy to chat).

The approach to CDG looked far steeper than other airliner approaches I had witnessed from the flight deck; more like one of my glide approaches in the Chipmunk! But it wasn't, of course, as we were following the 3 degree glideslope. I guess it was an illusion brought about by the steep pitch angle.

I remember the captain resting his hands on the throttles as they shuttled back and forth under autothrottle control, the smooth touchdown, the 'landing' of the nosewheel followed by full forward stick, and thinking "we'll never make that turn off". Then on came the powerful reverse and the brakes, I was thrust foreward in my harness, the speed disappeared, and we made the turnoff easily!

Oh, and that stange bouncy ride in the flight deck on the ground as the long nose forward of the nosewheel flexed over every joint in the taxyway. So bad at times it was difficult to take a photograph!

What an experience!

I have a question which I hope hasn't been answered in the pages (20 to this one) that I've yet to read.

From an earlier post I understand that the anti-skid used a rotational reference from the unbraked nosewheels to compare to the rotation of the mains, and that with gear down in the air a substiute nose-wheel referance is supplied which, because the mains are not yet rotating, allows the anti-skid to keep the brakes off.

But what happens when the mains touch down with the nosewheels still high in the air? What (if anything) inhibits wheel braking until the nosewhels are on the ground (and therefore rotating)?

Also, this thread started with a question about the lack of an APU. When Concorde was parked could the aircon and cabin lighting be powered by external electrical power, or did the cabin aircon without engine power require an external 'aircon unit' to be connected? Or was aircon simply not available without at least one engine running?

And one for Landlady or any other CC. If a table top was set up between the cabins during service, how did the 'front' crew service the first 2 rows of the rear cabin?

Being 'up front' for my entire flight, I missed out on the cabin service. But superb though I'm sure that was, under the circumstances it's not something I regret!

If you look at it from straight ahead it's not really a 'kink'.



From the angle the 'kinky' photo was taken the outer sweep of the ogee wing is towards the camera before sweeping aft to the drooped and washed-out tips and it looks like a kink in the LE sweep. The actual shape is seen better in the picture above. I've spent hours studying our G-BOAC at Manchester and to me the wing is a complex and lovely blend of curves and slopes, with no sudden changes such as a kink would require. Standing under the wing and observing it closely, no kink is apparent.

The wash-out on the tips shows particularly well in the above photo (washout is a forward twist of the wing at the tips to reduce the angle of attack of the tips compared to the rest of the wing, to prevent tip-stalling).

A question I have, relating to the photo above, is about the LE. The LE definately 'droops' in the area ahead of the intakes (it doesn't do so nearer the roots or tips). Is this to provoke a clean flow-breakaway in this area at high angles of attack to encourage the votices to form at this point as the wing transitions to vortex lift?

M2Dude Thanks for the kind words and careful explanations. I take it from your description of the anti-skid that once the mains start to rotate the brakes can be used, as the anti-skid comes 'off' (mains no longer think they are skidding).

I thought there was protection to prevent brake use until the nose wheels have landed, else brake application with the nose high would cause a rapid nose-down pitch, slamming the nosewheels on! Is there any such protection?

Many thanks CliveL and LL! Most informative!

The dreaded Pepsi scheme? Not on for long; it didn't help with skin temps for one thing. Even worse... it was hideous!

Serious question now. At 60,000 feet outside and 6,000 feet inside, what was the PSI pressure the cabin was subjected to? If I was clever I could probably work it out, but I'm not.

Many thanks CliveL and Dude!

She's always looked good, but probably didn't look any better in 1969 than she does now.

Cars are 'styled' and are therefore subject to fashion whims. So a car of 1969 looks awfully old fashioned by 2011 standards.

Concorde wasn't styled. She is the shape she is because that's the shape she needs to be to enable her to do what no other aeroplane could do - carry 100 shirt-sleeve comfort passengers at Mach 2 and 60,000' for up to 4.5 hours.

Concorde was form following function. Her beutiful lines did not come from a stylists drawing board, but from those of the aerodynamicist and other engineers involved in her design. So she hasn't dated!

Static ports are by no means unique to Concorde; all aeroplanes have them. They measure the air pressure around the aeroplane, and this value is used in various aspects of aircraft instrumentation. In particular, it is used (together with the dynamic pressure value) to display indicated air speed.

Dynamic pressure is what the pitot heads produce - those forward-pointing tubes either under the wings or (as in the case of Concorde) alongside and on the nose which simply measure the pressure of the air generated by the aircraft's forward movement through the air.

By the way - engine bay doors; we open one on OAC for our Technical Tours (not the shorter, 'Classic', tours where there wouldn't be time) so we can show the 593 Olympus and tell our visitors about it. Those doors certainly are heavy!

All 4 engines (and indeed everything else that BA left untouched on de-commission) are still in the airframe. She is pretty much as she was when she flew in on 31st October 2003.

Here is the only OAC engine bay pic I have. Must remember to take my camera next time I do a tour!

G-BOAC engine no. 1.

The 'blind' window is where the wardrobes are - no seats there. Also just about visible in that picture is the 'area ruling' of the rear fuselage where the fin starts - the fuselage is noticeably 'waisted' there.

Glad you enjoyed the event at 204, Dude. I have a lovely painting on my wall of G-BOAC on the roll-out on her last ever landing at EGCC 31st October 2003. It was signed all around the border by all the Concorde crews present that evening that I could cajole into signing, then I got it framed!

CliveL said "Sorry SSD, but there ain't no waisting on the fuselage, although the area ruling in that area is quite good. Did you mean where the fuselage starts to taper?"
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Nope. I meant the waisting of the fuselage where the fin starts. Stand on the steps by the front door where Dude's wife took that picture, and you'll see that the cabin roof is 'waisted in' noticably where the fin is mounted (not the sides of the fuselage which remain parallel - the roof, which is bowed inwards and downwards to reduce the fuselage cross section co-incident with the fin's extension above the fuselage). I see it several times a week on OAC.

You can see it on this picture too, though it's not as obvious as when you look back from the door.



Mr Vortex - Yes, the gradual taper of the nose and of the tail help with area rule. As does the wing leading edge being brought as far forward as possible where it joins the fuselage, so the cross-sectional area increases as gradually as possible, nose to tail, at the wing root.

I have seen an artist's impression from the '60s of a Concorde in RAF colours. As you say, by the time Concorde became available the high altitude bomber role had gone due to improvements in anti-aircraft missile performance.

Concorde would have been horredously inefficient at low level with a very short range, it isn't big enough to use as a military transport, so it's difficult to envisage a military role for it.

Dmussen, it is very strange to walk out onto the wing, isn't it? I, too have walked on AC's port wing and it seems to slope away from you in all directions! I didn't have the b@lls to venture near the LE! But I have seen it at close quarters from stepladders when helping to clean her when she first moved indoors at Manchester.

My favorite moment in that vid, too. I've seen two different 'edits' of it as well. One version ends "taking our service still higher and higher", the other "she's just a bird in the sky, and that is where she belongs", and there are other differences as well. But both contain those (supposed) take off shots with the nose at 12.5 degrees droop!

I was also told by an ex-Concorde pilot that they lost the 'yellow' system just as they pulled up from the Red Arrows formation and powered away!

The Yellow is the standby system, but wouldn't it possible to 'lose' it even if it wasn't actually in use?

No thrust vectoring. The secondary nozzles did go to 'divergent' setting from 'convergent' for supercruise, but the thrust was always in the same direction (rearwards).

If the thrust had been angled downwards, it would simply have induced a nose-down pitching moment. Most undesireable!

Just a note to say how excellent the Concorde lecture at RAeS on Tuesday was. Most informative and entertaining, and so good to meet so many Concorde folks again.

Very many thanks John and Roger!

During the take off roll there was a power check called (by the FE, I think). I've heard this on recordings and videos variously as "power checked" and "Power set". Assuming they are one and the same check, which is correct?

Thanks Brit 312. "Power set" it is, then. I was aware of the '3 reheat' possibility which is decided before T/O depending on T/O parameters ('is this a 3 re-heat day or a 4 re-heat day?').

On the P1 side of the cockpit is a small hinged piece of metal which can be moved to show '3' or '4'. This is set before flight depending on whether 3 or 4 re-heats are the acceptable minimum for take off that day, so if there is a re-heat failure on T/O, a glance at that indicator will show if it's OK to continue with '3 lit' or not.

All 4 reheats were selected 'on' before take off. They wouldn't actually light until the engine was up to a certain power, so the answer is 'no'. The power-limiting ensures no. 4's re-heat doesn't light below 60kts.

Watch a video of Concorde taking off which gives the view from behind. You'll notice no.4 light up marginally after the other 3 (but there's not much in it as it didn't take the aeroplane long to get to 60kts!).

Thaks Quax. So all 4 reheats should light about the same time, then, regardless of power limiting on #4? It does seem that #4 lags a fraction in vids I've seen.