April 27, 2012, 18:27:00 GMT
permalink Post: 7159571
Yep that's it.
Imagine it this way - the outside of the hull is hot and expands. The floor and other interior components, however, are about 100 degs cooler and so not subject to the same expansion. In a very simplified description, if you imagine the floor on rollers but attached at one end then you'll see a gap at the other end when the exterior hull stretches. That's the effect you see when the expansion gap appears aft of the FE's panel in supersonic flight. (The floor is, by the way, not just sitting on rollers.....)
Electrical looms had a little sag between fixed points if they were attached to 'expanding' parts of the airframe.
And so on.
It's amazing there was ever any hydraulic fluid left on board if you consider the stresses and aggro involved in routing the pipes and hoses.
Imagine it this way - the outside of the hull is hot and expands. The floor and other interior components, however, are about 100 degs cooler and so not subject to the same expansion. In a very simplified description, if you imagine the floor on rollers but attached at one end then you'll see a gap at the other end when the exterior hull stretches. That's the effect you see when the expansion gap appears aft of the FE's panel in supersonic flight. (The floor is, by the way, not just sitting on rollers.....)
Electrical looms had a little sag between fixed points if they were attached to 'expanding' parts of the airframe.
And so on.
It's amazing there was ever any hydraulic fluid left on board if you consider the stresses and aggro involved in routing the pipes and hoses.
Subjects (links are to this post in the relevant subject page so that this post can be seen in context): Hydraulic
April 28, 2012, 10:47:00 GMT
permalink Post: 7160441
No part of the skin will be warmer than the TAT probe, if that helps......
Subjects (links are to this post in the relevant subject page so that this post can be seen in context): TAT (Total Air Temperature)
May 04, 2012, 08:41:00 GMT
permalink Post: 7170659
Shaggy Sheep Driver:
Yes!
Yes!
Subjects: None
May 04, 2012, 17:15:00 GMT
permalink Post: 7171594
Minor correction, though: TMO was 127, not 128.
Subjects (links are to this post in the relevant subject page so that this post can be seen in context): TMO (Temprature Max Operating)
May 13, 2012, 22:19:00 GMT
permalink Post: 7188202
Layover: BA001 landed as BA002 was taxying out, so a there and back was impossible with those timings.
In the days of BA001,2,3&4 operations it was possible to operate BA002 JFK-LHR then BA003 LHR-JFK and this occasionally happened if there was a sudden crew shortage or other disruption.
I did it once and it was a heavy day's work.......
In the days of BA001,2,3&4 operations it was possible to operate BA002 JFK-LHR then BA003 LHR-JFK and this occasionally happened if there was a sudden crew shortage or other disruption.
I did it once and it was a heavy day's work.......
Subjects (links are to this post in the relevant subject page so that this post can be seen in context): LHR-JFK Route
February 01, 2013, 07:41:00 GMT
permalink Post: 7668648
From an occasional visitor:
I don't recall using landing data cards.... There may have been a version buried deep somewhere, but we generally just set the limits and did any necessary perf calculations.
Hope that helps.
I don't recall using landing data cards.... There may have been a version buried deep somewhere, but we generally just set the limits and did any necessary perf calculations.
Hope that helps.
Subjects: None
March 03, 2013, 20:22:00 GMT
permalink Post: 7724204
FALTAHAN -
I can answer just one of your earlier questions - the one about the turn initiation off 31L.
As Bellerophon noted in a distant earlier post, we 'bugged' 20ft on the rad alt for this departure. As one climbed through 20' the DH light would go out and, subject to the gear being selected up, and V2 being achieved (that normally happened at about the point of lift-off), and a definite positive rate being achieved, the turn was initiated then. In deference to the low level we rolled gently, 6secs to achieve 25 degrees, but it's still a great testament to the handling qualities of this machine that we would initiate this turn - in any weather - at a height I'd be most uncomfortable if doing the same thing in a single-engined tourer.
So - in short - forget QFE; the answer is a height of 20ft.
Hope the PPL is coming along well, keep us posted.
I can answer just one of your earlier questions - the one about the turn initiation off 31L.
As Bellerophon noted in a distant earlier post, we 'bugged' 20ft on the rad alt for this departure. As one climbed through 20' the DH light would go out and, subject to the gear being selected up, and V2 being achieved (that normally happened at about the point of lift-off), and a definite positive rate being achieved, the turn was initiated then. In deference to the low level we rolled gently, 6secs to achieve 25 degrees, but it's still a great testament to the handling qualities of this machine that we would initiate this turn - in any weather - at a height I'd be most uncomfortable if doing the same thing in a single-engined tourer.
So - in short - forget QFE; the answer is a height of 20ft.
Hope the PPL is coming along well, keep us posted.
Subjects (links are to this post in the relevant subject page so that this post can be seen in context): V2
October 18, 2013, 06:51:00 GMT
permalink Post: 8104933
The windows are tiny
cockpit is blocked off with clear Plexiglas, but looked decidedly primitive by todays (or even 1980's) standards
There's not a lot of space for the necessary controls in the front of a pointy aeroplane, and this was done in era when the appearance of the flt deck was inconsequential compared to its efficiency, utility and safety. It's only from the beige cockpit Boeings and onwards that the trend has emerged to for all these swoopy trim panels to be fitted for cosmetic reasons.
As for commercial failure - that may be true for the constructors but I can assure you that there's no way BA would have been flying them if they didn't contribute to the bottom line, let alone invest in the return to service programme.
It always pays to remember the context of operation of this machine when making comparisons with conventional aircraft,as that's what drove much of the design.
Subjects (links are to this post in the relevant subject page so that this post can be seen in context): British Airways
October 23, 2013, 20:03:00 GMT
permalink Post: 8114029
'Dry' thrust was used for a go-around, except in the case of wind shear when 'contingency' was used. (A bit more than full thrust and reheat).
Subjects (links are to this post in the relevant subject page so that this post can be seen in context): Afterburner/Re-heat
December 06, 2013, 01:41:00 GMT
permalink Post: 8191050
..... not convinced that theory's true.....
The PFCUs will offer a lot of damping, even while unpressurised. I've never seen a control surface 'slam' side to side on a hydraulically powered aircraft for tis reason.
The cause of the rudder failure was internal corrosion brought about by a mod which added a fillet to the trailing edge.
I suggest the surface winds were a red herring.
The PFCUs will offer a lot of damping, even while unpressurised. I've never seen a control surface 'slam' side to side on a hydraulically powered aircraft for tis reason.
The cause of the rudder failure was internal corrosion brought about by a mod which added a fillet to the trailing edge.
I suggest the surface winds were a red herring.
Subjects (links are to this post in the relevant subject page so that this post can be seen in context): Corrosion Rudder
February 22, 2014, 10:14:00 GMT
permalink Post: 8333226
For the AICUs perhaps?
Subjects: None
March 13, 2015, 09:29:00 GMT
permalink Post: 8899992
Just happened to look in, and saw this thread was active again.
No trouble getting down from the CRZ:
Idle power would be used (the ramps should cope with the change of airflow). Idle power at M2 resulted in a most impressive rate of deceleration (anyone standing in the aisle would probably find themselves sitting), which translated into a very high RoD. Well over 10 000fpm initially.
As such, reverse would be neither needed nor desirable; you would be well outside the envelope of idle reverse use anyway. (This function was quite rarely used as it was a bit of a faff).
The pilots would select the fuel fwd transfer override switch initially to cope with the decel, and the FE would set the fuel panel up shortly after the descent was steady.
All very dramatic, and never needed in pax service afaik .
No trouble getting down from the CRZ:
Idle power would be used (the ramps should cope with the change of airflow). Idle power at M2 resulted in a most impressive rate of deceleration (anyone standing in the aisle would probably find themselves sitting), which translated into a very high RoD. Well over 10 000fpm initially.
As such, reverse would be neither needed nor desirable; you would be well outside the envelope of idle reverse use anyway. (This function was quite rarely used as it was a bit of a faff).
The pilots would select the fuel fwd transfer override switch initially to cope with the decel, and the FE would set the fuel panel up shortly after the descent was steady.
All very dramatic, and never needed in pax service afaik .
Subjects: None
March 18, 2015, 08:30:00 GMT
permalink Post: 8906242
Time for descent may well have been a certification requirement for max FL - others will know better than I…
I don't believe the ramp schedules were designed to operate far above FL600, I vaguely recall that FL635 was the highest reached during testing but, again, others will know better. A typical LHR-JFK or JFK-LHR would get to between 570 and 590 depending on weight and OAT, LHR-BGI almost invariably ended up level at FL600 due to lower weight and much lower outside temps.
As for reverse inflight, off the top of my head the limits were; Max FL300, speed 250-380kts, max use 4 mins. It didn't make a vast difference to RoD, although it was noticeable.
Inflight rvs was limited to engs 2 and 3 but to enable sufficient air to deploy the reversers, engs 1 and 4 spooled up slightly (in fwd thrust) to help deployment. While this is going on the primary nozzles open fully (for the same reason) but after reverse position is reached, the 2 and 3 primary nozzles have to close to 15% otherwise you get a 'CON' light which means reverse has to be cancelled on that engine (this was not a rare event).
Common sense and airmanship also dictated that you had an escape plan if one or both the engines didn't get the secondary nozzles out of reverse, so you didn't want to do this if fuel was tight.
All-in-all it was far better to make sure you didn't need reverse inflight!
I don't believe the ramp schedules were designed to operate far above FL600, I vaguely recall that FL635 was the highest reached during testing but, again, others will know better. A typical LHR-JFK or JFK-LHR would get to between 570 and 590 depending on weight and OAT, LHR-BGI almost invariably ended up level at FL600 due to lower weight and much lower outside temps.
As for reverse inflight, off the top of my head the limits were; Max FL300, speed 250-380kts, max use 4 mins. It didn't make a vast difference to RoD, although it was noticeable.
Inflight rvs was limited to engs 2 and 3 but to enable sufficient air to deploy the reversers, engs 1 and 4 spooled up slightly (in fwd thrust) to help deployment. While this is going on the primary nozzles open fully (for the same reason) but after reverse position is reached, the 2 and 3 primary nozzles have to close to 15% otherwise you get a 'CON' light which means reverse has to be cancelled on that engine (this was not a rare event).
Common sense and airmanship also dictated that you had an escape plan if one or both the engines didn't get the secondary nozzles out of reverse, so you didn't want to do this if fuel was tight.
All-in-all it was far better to make sure you didn't need reverse inflight!
Subjects (links are to this post in the relevant subject page so that this post can be seen in context): LHR-BGI Route LHR-JFK Route Nozzles
March 19, 2015, 12:55:00 GMT
permalink Post: 8907905
\x85\x85it was pumped.
Tank 11 also had two hydraulically-powered fuel transfer pumps to cater for other failures which may deprive you of elex power to the usual pumps, just to cover all eventualities.
Tank 11 also had two hydraulically-powered fuel transfer pumps to cater for other failures which may deprive you of elex power to the usual pumps, just to cover all eventualities.
Subjects: None
March 20, 2015, 04:30:00 GMT
permalink Post: 8908683
Nope. Don't remember ever doing that.
Occasionally tech stopped ANU or SMA if tight for fuel.
Occasionally tech stopped ANU or SMA if tight for fuel.
Subjects: None
April 08, 2015, 19:40:00 GMT
permalink Post: 8937224
Ruddman -
No autobrakes.
(And - with my pedant's hat on - no 'manual' brakes either. Pedal brakes, yes. I know that the 'manual brakes' has become an accepted term, but the nonsense of it just bugs me….)
Stopping distances were good; from a higher Vapp we stopped rather shorter than a 'classic' 747. Filton was tightish, Bournemouth was worse….
First gen carbon brakes did not like being 'feathered' so we used them pretty firmly on every landing. At Filton, Bournemouth, E Midlands etc. you'd put the pedals to the floor after nose wheel touchdown. Allegedly no more wear doing this than feathering them along a long runway.
Reverse was pretty effective - more so than a modern bypass engine. We idled the outboards at 100kts and the inboards at 75kts so they weren't in play for the whole landing (reverse is most effective at higher speeds anyway).
It was a good 'stopper'. Thankfully.
No autobrakes.
(And - with my pedant's hat on - no 'manual' brakes either. Pedal brakes, yes. I know that the 'manual brakes' has become an accepted term, but the nonsense of it just bugs me….)
Stopping distances were good; from a higher Vapp we stopped rather shorter than a 'classic' 747. Filton was tightish, Bournemouth was worse….
First gen carbon brakes did not like being 'feathered' so we used them pretty firmly on every landing. At Filton, Bournemouth, E Midlands etc. you'd put the pedals to the floor after nose wheel touchdown. Allegedly no more wear doing this than feathering them along a long runway.
Reverse was pretty effective - more so than a modern bypass engine. We idled the outboards at 100kts and the inboards at 75kts so they weren't in play for the whole landing (reverse is most effective at higher speeds anyway).
It was a good 'stopper'. Thankfully.
Subjects (links are to this post in the relevant subject page so that this post can be seen in context): Braking Filton Landing Gear
April 22, 2015, 13:52:00 GMT
permalink Post: 8952197
I've no idea about testing, but in line operations the Vmo peaked at 530kts, having started off rather lower depending on alt and mass. (Normally 380-400). I'm pretty certain there's at least one flt envelope earlier in this thread.
VAPILOT is spot on regarding the reasons for Vmo, of course.
Doesn't answer your 'during flight testing' question, I concede. Sorry!
VAPILOT is spot on regarding the reasons for Vmo, of course.
Doesn't answer your 'during flight testing' question, I concede. Sorry!
Subjects (links are to this post in the relevant subject page so that this post can be seen in context): Vmo
June 14, 2015, 10:34:00 GMT
permalink Post: 9011074
NineEighteen -
9mins brake release to M1.0 sounds about right from SNN; out of JFK we consistently achieved M1.0 10mins after brake release and that was with a noise-abatement departure which added a little time.
9mins brake release to M1.0 sounds about right from SNN; out of JFK we consistently achieved M1.0 10mins after brake release and that was with a noise-abatement departure which added a little time.
Subjects (links are to this post in the relevant subject page so that this post can be seen in context): JFK
December 08, 2016, 11:36:00 GMT
permalink Post: 9602910
Fraser -
You are correct, the INS's had a access to a separate memory facility in later years of operation. The access method is as you described, and then a numerical entry to access the relevant part of the route (or Flight Plan Segment), which would be numbered between 01 and 87.
The comms log would list the appropriate FPS number. Obviously, it was still possible to enter all waypoints longhand.
It was also possible to access a DME lat/long database using the same system which enabled DME updating and saved a lot of finding/typing Lat/Long for DMEs. (These were numbered between 90 and 99).
FWIW there was a specific Delco variant for supersonic flight (Delco IV-AC). It was permissible to have a 'standard' IV or IV-A in the number 3 position. IIRC the aircraft would be restricted to subsonic flight unless there was a IV-AC in both 1 and 2 positions.
Before my time, I believe there was a card reader system to do a similar job.
Stilton -
It did have a well-disguised FMA..... the Mode Select Panel was also the FMA. Lit button = active mode.
You are correct, the INS's had a access to a separate memory facility in later years of operation. The access method is as you described, and then a numerical entry to access the relevant part of the route (or Flight Plan Segment), which would be numbered between 01 and 87.
The comms log would list the appropriate FPS number. Obviously, it was still possible to enter all waypoints longhand.
It was also possible to access a DME lat/long database using the same system which enabled DME updating and saved a lot of finding/typing Lat/Long for DMEs. (These were numbered between 90 and 99).
FWIW there was a specific Delco variant for supersonic flight (Delco IV-AC). It was permissible to have a 'standard' IV or IV-A in the number 3 position. IIRC the aircraft would be restricted to subsonic flight unless there was a IV-AC in both 1 and 2 positions.
Before my time, I believe there was a card reader system to do a similar job.
Stilton -
It did have a well-disguised FMA..... the Mode Select Panel was also the FMA. Lit button = active mode.
Subjects (links are to this post in the relevant subject page so that this post can be seen in context): Concorde Routings
February 03, 2017, 17:35:00 GMT
permalink Post: 9663723
I didn't find any problems in strong headwinds.
We used to use Vref+10 instead of Vref+7 if it was windy (which made a bigger difference than the numbers may suggest) and, if anything, this made it easier.
We used to use Vref+10 instead of Vref+7 if it was windy (which made a bigger difference than the numbers may suggest) and, if anything, this made it easier.
Subjects: None