18 hours ago, Ray Proudfoot said:

CG should be 53 for landing. Easy peasy

for  some  of  us  Ray,   thats  why i left  it  to  the  VFE 🙂

15 minutes ago, pete_auau said:

for  some  of  us  Ray,   thats  why i left  it  to  the  VFE 🙂

If you get things wrong during a flight just turn the VFE / Fuel option back on.

I seem to remember in school being told that it takes 4x the energy to double speed or something to that effect. It doesn't bode well for having supersonic commercial aircraft that would make economical sense (or ecological as well I suppose). I think engineers have found the sweet spot for now. jmho

2 hours ago, rjquick said:

I seem to remember in school being told that it takes 4x the energy to double speed or something to that effect. It doesn't bode well for having supersonic commercial aircraft that would make economical sense (or ecological as well I suppose). I think engineers have found the sweet spot for now. jmho

Not sure this is still valid for supersonic flight. Anyway you also have to take into consideration the reduced crew etc. costs, reduced by almost 50% due to the less flight time. That combined with most likely very high ticket prices might make this viable if maintenance costs etc. can be kept in check. But personally I agree with you general point of view and think that we won't have supersonic commercial airliner flights anymore.

I reckon that if we never have supersonic commercial flights ever again, it will be because we are having hypersonic flights instead. When has human endeavour ever stood still?

40 minutes ago, Christopher Low said:

When has human endeavour ever stood still?

Since late October 2003 it hasn’t stood still. It’s gone backwards. From Mach 2.0 to Mach 0.85 in 24 hours. That was nearly 20 years ago. Since then… what? Diddly squat!

The lack of progress is shameful. The only time in aviation history there has been no progress.

You even have autopilot systems on a modern aircraft that allow two pilots to simultaneously make opposite inputs to the aircraft’s surface controls and end up trying to climb out of a stall and crashing. The same company whose earlier employees designed Concorde’s autopilot system.

Look at Concorde. Does it look like a 50 year-old design? Does it heck!

Buy Concorde. There will never be another commercial supersonic aircraft in my lifetime or others.

Human endeavor. I have often thought about the fact that most everything that is around today was already there (in some form) when I was born in 1964 (58 yrs). Cars, planes, men in space, computers, even ARPA was already being worked on (the beginnings of internet type technology). Yeah, there are improvements in all those things, but they're not new. I then compare that to someone being 58 in in the year 1964 and what they saw developed. They grew up to see the development of things that only existed in sci-fi books and magazines. We tend now to focus on making refinements in things to get you to replace your old one. As a kid, the representation of the new millennium (the year 2000 seemed so far off) was one of flying cars and pristine, ultra clean cities all powered by some yet unknown energy. The reality is most of the infrastructure that was newly built then is still being used, but is falling apart now. Anyway, I'll stop now... We do have microwaves now though. That's new 🙂.

Pardon my diversion.

Well, the cheese has clearly slid off the cracker on this topic …. sorry Bernard! I tend to be a little more optimistic about the future in terms of what could be and can be, including supersonic flight. Simply because we only understand what is possible with our present day knowledge. Evolving discoveries in science shape how we think and what is possible. What seems very complicated today as a result of limited knowledge can turn very quickly into simpler solutions with breakthroughs in the field and associated technologies. If deep pockets exist with the will to see something succeed, it will eventually. Perhaps not following a well laid out blueprint, but with some curves along the way to see what a prototype can do.

Let’s try and push the cheese back on the cracker! Who knows, perhaps there will be developments in flight simulation code and modeling that will accelerate porting between different platforms! Remember that quote by a very famous scientist “imagination is more important than knowledge”.

11 hours ago, Ray Proudfoot said:

Look at Concorde. Does it look like a 50 year-old design? Does it heck!

Not from the outside, maybe.

Regarding your other point, I'm not aware of any autopilot which allows contradictory input from different pilots, although most aircraft, even those with yokes, will allow differing input to the flight controls.

Edited May 24, 20233 yr by ConstVoid
Extra Info

It may have looked 10 years ahead of itself when it was originally designed but there is nothing that screams 1970's more than Concorde. Except for maybe a kipper tie. It looks just as anachronistic as it actually is. 

51 minutes ago, St Mawgan said:

It may have looked 10 years ahead of itself when it was originally designed but there is nothing that screams 1970's more than Concorde. Except for maybe a kipper tie. It looks just as anachronistic as it actually is. 

You do realise all supersonic aircraft require a delta wing in order to fly beyond Mach 1 and be able to safely fly at lower speeds below 10,000ft.

Boom will have a delta wing. I find your use of the word anachronistic astounding.

1 hour ago, ConstVoid said:

Regarding your other point, I'm not aware of any autopilot which allows contradictory input from different pilots, although most aircraft, even those with yokes, will allow differing input to the flight controls.

Air France Flight 447. Whilst the a/ p was disconnected the crash was down to the flight crew. I accept any autopilot should disconnect once manual inputs are detected.

With a side stick as opposed to a yoke neither pilot was aware what the other was doing.  https://en.wikipedia.org/wiki/Air_France_Flight_447

Opinions differ re AF447, but insufficient training and panic may have been a major factor. There would certainly have been 'dual input' warnings on the displays to alert the pilots to this. Even in the B777 it is possible, with some effort, for the captain and first officer to provide opposing control inputs, such that the torque tube linking the yokes disconnects (by design). If that happens in a panic situation each pilot might not be aware of the other pilots actions either.

@ConstVoid, we’re drifting off topic so this will be my final reply.

Training and operational standards at AF were pretty poor. Need I mention the Concorde crash and all the things that were or weren’t done that contributed to the accident?

At least with yokes the captain and first officer should be aware of what, if anything, the other is doing. What about “I have control, you have control” that should be mandatory on all commercial flights.

That AF447 crew should never have been left together without someone more experienced in the flight deck.

14 hours ago, Christopher Low said:

I reckon that if we never have supersonic commercial flights ever again, it will be because we are having hypersonic flights instead. When has human endeavour ever stood still?

Business travel was the primary driver for the continued existence of Concorde. In the end it operated almost like a private jet with relatively low passenger volumes and high ticket prices. It was set this way because offering another level of business travel was the only way to justify high ticket prices to meet the running costs. Had it not been for the British/French governments subsidising loss-making production then it wouldn't of existed in the first place.

You can do the math relatively simply. Concorde typically used around 93t of fuel for London-New York which is ~115,000 litres. At today's prices that would cost you £130,000 for fuel. Let's also say that Concorde is running that flight with 120 passengers. That's £1,000+ per ticket just to break even on the fuel whilst ignoring all other costs. To account for all other costs that £1,000 would become perhaps more like £3,000-£5,000 which is excessive and you don't get a lie-flat bed either. You can absolutely forget economy fares.

It's these economics that killed Concorde and those same economics haven't changed unfortunately and they will kill any future supersonic/hypersonic aircraft too unless the technology is radically different. That being said it was an incredible aircraft however I view it in the same way of the Space Shuttle, great machines but really bad ideas.

Edited May 24, 20233 yr by G MIDY