Quiz - What was the Worlds fastest subsonic airliner?

[twistedenginestarter]

This airliner was reported in 1971 to have Vdf (max demonstrated) of 445 knots and Mdf 0.97, and according to DP Davies in Handling the Big Jets had been flown by the designers at Mach 0.99 "and it is understood that it still handles remarkably well". You can't get any faster that that without becoming supersonic.

What was this superstar airliner and what happenned to it?

[Mode Charlie]

VC10 perhaps ?

[twistedenginestarter]

Sorry chaps - No.

This aeroplane had hardly any mach buffet affects and could despatch with all roll dampers inoperative - it simply didn't dutch roll.

Any more guesses?

[Roger Turbojet]

Dont know if it is true, but I belive to have read a L1011 have flown .95

I was in relation to the Citaion X, where many was impressed how fast it could fly. Some guy wrote that it was not so impressive, as he had done .95 in a L1011, but fuel economy was a different storry....

[Stampe]

My money either goes on the VC10 I was overtaken on the North Atlantic once by an RAF one going at a hell of a lick whilst creeping along in 767,or most probably the Convair CV880/990 family which is now extinct but looked much like an early DC8.I think they were called coronados and were extremely quick.Progress has stopped bar avionics and engines!!.

[VnV2178B]

Stampe,
I place my money with yours on the Convair. I recall when it was first proposed (God, am I really that old!) it was billed as the fastest airliner available - by the marketing department. The poor old designers and engineers who put it together were then forced to resort to all sorts of refinements to get it to achieve the promises. Plus ca change eh!

VnV...
Whatever happened to progress ?

[Genghis the Engineer]

I must admit I'd have guessed the VC10 too, but failing that...

Wasn't the Comet with it's pure turbojets was it?

On the other hand, if it was just coming into service in 1971, that would be the right date for a 747 Classic.

G

[This message has been edited by Genghis the Engineer (edited 15 January 2001).]

[Cornish Jack]

By all accounts - not personal knowledge - the Convair 990 was the fastest of it's peer group. If I remember correctly, the VC10 was taken (inadvertently) up to the high .9s but became a little 'modified' in the process!!

[twistedenginestarter]

This is slightly a trick question. The Mach 0.99 I refer to is in a dive. It is not something the plane could maintain unless some distinctly bigger engines were strapped onto it.

The interesting thing is it could do 0.99 without any control complications.

As a clue, a significant contributory factor was the presence of large fully powered control surfaces avoiding the compromise between effectiveness and stick force.

[Eff Oh]

Was it the Trident??

[Groundloop]

Douglas once flew a DC-8 at over M1.0 on a test flight (in a dive, of course). Aircraft was then delivered to Canadian Pacific and carried a small plaque noting that it had gone supersonic.

[18Wheeler]

It's the trusty old 747!

It was tested in a dive to M 0.991 in the original certification tries, just to test for mach tuck.
FWIW, I've seen M 0.88 fairly sustained in the cruise .... we were in a hurry!

The fastest cruiser though, I think, was the Convair 990 (??) Did something like M 0.9 sustained.

[quid]

Was it perhaps the B-747 SP? Short fuselage, very long range.

[twistedenginestarter]

First prize goes to 18Wheeleralthough Genghis was on the scent.

It was indeed the 747. Described by the author as [i]an airship with wings on it[/].

I find it fascinating that an everyday plane can be made to go at Mach 1. That's a significant chunk off a long haul journey time albeit at considerable extra fuel expense no doubt. Goes back to earlier discussions on why jets still don't fly faster. There are plenty of engines above 50000 pounds that could get the 747 cruising faster.

I wonder what it would take to hold Mach 0.99 at 40000 feet?

[DCDriver]

As a copilot I used to fly with skippers who'd flown the Convairs, both the '880 and '990. I remember them saying that the normal cruise Mach was 0.92 but as fuel was cheap in those days they would simply accellerate until the bell rang, then ease the power off a bit. I think Mmo on the '990 was .96 or .97 after they fitted the "Kucheman carrots" on the wings to cure the prohibitive drag penalties discovered in flight testing.

[Airbanda]

Spotters books in the seventies and Guiness always quoted the CV990 Coronado as the fastest subsonic cruise with the Trident close behind and fastest british machine.

Are the ex Spantax 990's still decomposing at Palma?, think I remember seeing one execute a smoketrailing departure from LBA in 85. There is/was a beatifully preserved Swissair example in the Swiss transport museum at Lugano, landed at an airforce base across the lake and then floated over on pontoons.

[Jetdriver]

Convair 990 "Coronado" !
Built by General Dynamics in San Diego California.

Prior to Concorde,it was the biggest financial disaster in aviation history nearly bringing General Dynamic to its knees. Convair lost $250 Million, 37 were built. Flew with Swissair and Spantax, but devolped for an American Airlines requirement.

CV 990 featured 4 "Area Rule" conical fairings on the wing trailing edges. The 990 was a devolpment of the smaller CV880 which operated for Delta, Cathay Pacific and others.

990 was powered by 4 GE CJ805-23B Engines
Accomodated 106 pax typically.

[18Wheeler]

Nah, no 747 could get close to M 1.0 in level flight - The one that did the M 0.991 run had about 10° nose down, I think, to get up to that speed.
In one of the previous companies I worked for, one night out in the middle of no-where, the 747 (I wasn't on board) got hit with a big standing wave, and in a few seconds the mach number went from 0.85 up to 0.96 on the ASI!!
(Mmo 0.92) The Captain kept his cool and just pulled the power back, and let the speed bleed off over a minute or so. An airframe inspection revealed no damage at all.
I think about the fastest you could go in, say, a Roller powered -200 would be about M 0.9 or so, depending on the weight, temp, and altitude.

Here's a pic of one of the 747-100 (PW 7A powered) I flew that got caught in a small standing wave - we were doing 0.84 a few seconds before that ...

http://www.onthenet.com.au/~billzila/highmach880.jpg

Didn't feel a thing ... :)

[This message has been edited by 18Wheeler (edited 16 January 2001).]

[Roger Turbojet]

....godd*m......

[twistedenginestarter]

10 degrees nose down and full power? Right I should now be able to go away and calculate what engines would be needed to keep it up all day...

[Stampe]

Some of us seem to have missed the point its not one off test flights or dives,its cruise in routine service and it looks to me as if the Convairs might have it.Airbanda I think all the old Spantax Convairs at PMI have gone one lingered on longer than the others but I can,t remember seeing that recently I,ll remember to lookout for it on my next turnround it was behind the military hangar adjacenr to the 24R threshold.

[twistedenginestarter]

I'm not disputing the Convairs were able to cruise faster but my original point stands. The old obsolete 747 could fly at Mach 0.99 which was a creditable aerodynamic achievement.

If it was at 10 degrees and say at full power... let's say the engines produce 60% power at cruise altitude. Sine 10 degrees on 300 tonnes gives us 28750 pounds per engine. Factor that by 100/60 and add to the 50000 pound engines it's already got and that means you'd need four 98000 pound engines to turn your 747 into a Mach One Cruiser. ;)

Dear Rolls Royce...

[18Wheeler]

FWIW, the early 747 A's used the P&W 7A engines, which has a mere 43,000 lbs of thrust. I know this, because I have to fly the blasted things ... :)
That picture above is in one of them.

[411A]

Turbofan engines typically produce less than 60% of rated thrust at normal cruise altitudes. The 747 was designed to cruise at M.86 and as such has 39 degree swept wings. The L1011 was also designed to cruise at M.86. The CV990 was designed to cruise at M.90. Older is faster, but more thirsty.

[18Wheeler]

411A - close! ;) The 747 was originally designed for M 0.84, with the -200 at M 0.85, and the -300/400 at M 0.86.
The wing sweep is 45°.

Um, unless I'm wrong ... ;)

[ShyTorque]

You are all wrong.

The fastest subsonic airliner flew at Mach 0.999999 recurring.

Easy - it was Concorde just slowin' down at idle.

P.S. Just thought of something else. It was (is) so far ahead of its time it was even designed to counter the "Economy class" DVT problem. Due to air friction the legroom increases as it reaches Mach 2!

[This message has been edited by ShyTorque (edited 16 January 2001).]

[Airbanda]

Maybe this does not qualify, but according to Stanley Stewart's "Emergency" a TWA 727-31 involved in a serious incident over the great lakes in April 79 actualy broke the sound barrier. There is a lot more to say about the causes of the incident but I will leave that to those better qualified than myself!

[Dave Incognito]

Along a simmilar thread, the Silk Air (sp?) 737 that crashed a couple of years ago when the Capt. nosed the aircraft into the ground (with full power) was doing something in the region of Mach 1.3 upon impact. All because of the actions of one crazed man.

[Juliet November]

I've actually had the pleasure of flying the CV990 Coronado. Unfortuneatly I was only 1 year old, but according to my dad it did CPH-MAD in less than 3 hours. Probably had some favourable tailwinds, but that's still around 30 - 45 mins. less than a current day MD80 with SAS or Iberia.

The best part though, unless you're a treehugger, was the smoketrail it left on take-off. Rumours has it that a clever ATCO fellow actually issued a RVR on the ATIS after a Coronado had taken off :)

It even made a Phantom bluss from embarresment !

[scroggs]

I think for serious subsonic cruise one-upmanship, you'd have to go a long way to beat the old RAF Vulcan B2 and Victor B2, bothof which could cruise at M0.90+ at FL550 or higher.... The RB211 B742 is quite happy at M0.88, and I've seen M0.90 briefly. The VC10, I think, had a high-speed cruise of M0.94, but with all the growths they've sprouted in the military I doubt they can do more than M0.85 now.

[twistedenginestarter]

Apologies to quid. Your answer crossed in the post.

I have cruise Mach 0.92 for the 747 SP. Not sure how reliable that figure is.

Here's a question - When the 747 was doing Mach 0.99 every airflow was presumably supersonic so would it have generated a sonic boom?

[18Wheeler]

twistedenginestarter - Nah, the SP (Short Plane :) ) sits on 0.86, but yes, it can go a lot faster if you like.

And a cautious yes to the question of sonic boom, albeit a relatively quiet one with the 747 at 0.99. Being a subsonic speed, it's not entirely supersonic over the entire airframe, so it wouldn't have a completely developed shock wave.

[Dr. Red]

http://pprune.homestead.com/files/Nwadc10.jpg

Photoshop monster!

[Shore Guy]

Anyone have any good links for the 880/990?

Here are some for pictures of TWA's

* Trans World Airlines (TWA) Convair CV-880 N805TW (SFO)
http://airliners.net/open.file?id=104725
* Trans World Airlines (TWA) Convair CV-880 N819TW (DEN)
http://airliners.net/open.file?id=95634
* Trans World Airlines (TWA) Convair CV-880 N819TW (BOS)
http://airliners.net/open.file?id=48534
* Trans World Airlines (TWA) Convair CV-880 N819TW (BOS)
http://airliners.net/open.file?id=35034

[Horsepower]

Coincidentally, this has just appeared on AP.

BOEING STUDIES BLUEPRINT FOR SUPER-FAST PASSENGER JET
Boeing - the US company that developed the world’s fastest jetliner - is looking at a new commercial plane that could fly at nearly the speed of sound.
Boeing spokeswoman Barbara Murphy confirmed that the company was studying the concept, referred to internally as “Yellowstone”, but would not give specifics. No decision has been made on whether to actually develop the aircraft.
The Wall Street Journal, quoting unidentified sources, reported that the jet would be capable of travelling at Mach 0.95 - Mach 1 is the speed of sound.
The jet would carry 200 to 300 people as far as 6,100 nautical miles, similar to Boeing’s two-engine 767s, the Journal said.
The fastest subsonic commercial jet is Boeing’s 747-400, which can fly at Mach 0.92 but cruises at Mach 0.85, or more than 500 mph.
The Concorde supersonic jet can fly twice the speed of sound and crosses the Atlantic at 1,350 mph. The Anglo-French plane has been grounded since an Air France Concorde crashed on July 25, killing all 109 people on board and four people on the ground.
Murphy said Seattle-based Boeing constantly studied new designs and materials for possible future use under its 20XX program.
She said Yellowstone was part of the 20XX and the P-2 research programmes. P-2 refers to a design that looks similar to Boeing’s 777 twin-engine wide body, but could be any size from a 100 to a 600-passenger jet and includes many configurations, she said.
Boeing has long studied a possible new supersonic transport, but breakthroughs in materials and engine performance need to be made for the aircraft to be economically practical, she said.
“We do not see, at this point, anything on the horizon that is going to change this problem with faster speed and poorer economics,” Murphy said.
Murphy noted that improvements for the proposed 747X family, which would compete with the recently launched Airbus Industries 555-passenger A380 jet, would allow it to cruise at Mach 0.86. So far, Boeing has not received any orders for the 747X. Such tiny increments are important, especially on long-range aircraft, since they allow more efficient, economical flights.
In 1966, Boeing won money from the government to develop the SST, or the Supersonic Transport, which was expected to become the American equivalent to the Concorde, said Boeing historian Mike Lombardi. However, the project was cancelled in 1971 due to costs and objections over possible environmental impact, he said.
Lombardi said Boeing had continued to study travelling at supersonic speed. Until three years ago, the company worked with Nasa on the High Speed Civil Transport programme. The program ended, he said, because “they found that the planes wouldn’t be economical to operate, and they still had to overcome the hurdle of a sonic boom”.

[airforcenone]

Sorry to bash the Yanks, but apparently the Tu-154 (big Russian Trident) is quite quick. 0.94 in the cruise allegedly, although statistically, you may not live to see it twice ....

[lymanm]

Dr Red -
nice pic...slats deployed too! Vfe of 489kts ;-)

[Juliet November]

airforceone;

Good point. Historically the russians have produced some aerodynamic marvels, so maybe the fastest sub-sonic jet should be sought outside the usual circles ? Might prove difficult on this forum though; doesn't strike as the place where Aeroflop pilots hang around when off-duty....

[Ex Bus Driver]

Time for me to jump in...When I was hired @ AAL in Feb 1966, I was trained initially as
F/E on the CV-990. At the time, it was touted as the fastest airliner, based on MMO of .912. When AAL bought these aircraft, it was based, in part, on Convair's promise of the fastest airliner. To achieve this, various configurations of "anti-shock bodies" were tested (I've seen pictures of as many as seven/wing). The two/wing config
achieved the best results.
A few interesting sidelights to all this:
The outboard "ASB's" carried fuel (I can't remember how much). This fuel was burned in the climb so as to avoid a cruise limitation of M .78 with fuel in the ASB's!
The drag curve increased so rapidly that if one were cruising at .85 (typical), without touching the throttles you could nose over to a descent rate of 1500'/min and the speed would increase only to about .88!
It had alot of quirks, too many to mention here, but it was proof that Mickey Mouse was alive and well desiging planes for Convair!
Cheers, EBD

[Dan Winterland]

A B Cal VC10 once went supersonic after a jet upset crossing the Andes. A panel was missing from the tail area, other than that it was OK.

BOAC used to cruise the VC10 at .88 when fuel was cheaper. The RAF does a more leusirely .82

[Jim lovell]

Convair 990- VERY FAST AIRPLANE!!

[Speedbird48]

It was the Convair 990 Coronado although the Trident was not far behind.
The Comet was only a .72/.75 airplane.
The VC10 would probably be capable of Mach 1 and one was rolled when the F/O got it wrong on a Dutch Roll exercise. Although to watch the horizontal though the periscope while that was happening would be rather exciting.
BOAC also had a 707-436 that they lost control of in the same exercise and that was recovered over the sea off the SW UK coast at a very low altitude. It is believed to have gone supersonic as they pulled over the top on recovery.
But the fastest was indeed the Coronado and they have all gone now after Spantax got rid of them.

[pigboat]

I've got a book on the history of CP, and the author sez the DC-8 dash 43 was flown supersonic. The -43 had RR Conways instead of the Pratts. Dunno how true that is.

[DCDriver]

It is true, the DC-8-43 had RR Conways(as did some 7-oh variants inc BOAC's)and it exceeded Mach 1 in a shallow dive during a test flight.

[Pdub]

They all worked mate, you need to refresh your browser sometimes in order to see postings that are very recent. pressing shift + refresh symbol works to force a refresh and not used a cached version of the page

and also no matter what your browser does don't use the back button to go back to the submit page and press submit again, chances are that your submission was taken , but that your browser went funny after that. Easiest way I find is to highlight what I have written then copy it so I can paste it back if neccesary, saying that I've never found that my post hasn't gone through, except when I've put my password in incorectly.

[This message has been edited by Pdub (edited 29 January 2001).]

[GotTheTshirt]

Isnt that a Convair 880 ? across from the runway at Lisbon.

It now has scantily clad girls cavorting in the back - so nothings changed there then !

[411A]

SPEEDBIRD 48
You are quite correct. CX had a fleet of CV880's. And indeed the CV990 was the fastest in normal cruise. Several I have noted earlier have the incorrect information about wing sweep. Boeing 707, L1011 are at 35 degrees. DC-8 (-20 series, the first to go supersonic) is 30 degrees. The Boeing 747 is at 39 degrees. There is no western 45 degree swept wing subsonic airliner in service. And never has been.

[daft fader]

I only ever witnessed cv990s at an airfield. I seem to remember them being a bit fastish on the approach as giving an SRA to one was always "interesting" . They were extremely dirty looking on departure, quite often giving rise to jokes about needing RVR readings for following aircraft.

[Back Seat Driver]

How slow was the SUD-AVIATION CARAVELLE?

[highlandflier]

A couple of years ago I had a jumpseat ride in a an Avial TU154 from Moscow to Kogalym. In the cruise at 11700m over Siberia, we were indicating M0.97. The captain reckoned he could stand the power levers up a little bit more, but then I might start getting tunnel vision!

[Pdub]

AARRRGGGGHHHHH, No offence Speedbird48, but I think we have now established that Spantex used the Convair 990, and the Comet was only a .72/.75 airplane

[DCDriver]

Pdub, was "spantex" was what the Spantax girls wore under their uniforms? Due to the 990's high speed, of course..

[Smoketoomuch]

Speedbird!! You've been posting the same msg for over a week! Pleeeease, sort your pc/isp out.

[Pdub]

oops, I won't edit it as otherwise you'll look as silly as me DCDriver :)

[Jim lovell]

727 also relatively quick- mach .9?

[DCDriver]

....especially if you tinker with the slats in the cruise....
:) :)

[PPRuNe Radar]

To explain why some of the posts here might not make too much sense ........

I have removed 12 posts from Speedbird 48 which all said more or less the same thing. The advice about refreshing browser caches is sound and saves us a lot of work here at the Towers if followed ;)

------------------
PPRuNe Radar
ATC Forum Moderator
[email protected]

[epsom hold]

Not only is the CV990 the fastest (although the Tu154 info is interesting), but it set speed records which will never be broken, since it flew in the days before (a) the 250 kts below Fl100 rule was introduced and (b) there was no traffic, so crews would fly at breakneck speed direct to the outer marker. Certainly on almost every US domestic route the a/c was ever flown on, the speeds set by the CV990 are untouchable and will remain so forever.

[Tim Zukas]

Actually most of the US city-to-city records that AA set in 1961-65 were with their 707s, not their 990s.

[Speedbird48]

It was the Convair 990, Coronado last flown by Spantax and Nasa had one for a while. It could be told apart from the 880 by the big lumps on the trailing edge which reduced drag.
The Trident was also very quick but the Comet was only a .72/.75 airplane.

[Speedbird48]

It was the Convair 990, Coronado last used by Spantax, although NASA did have one for a while. Can be told apart from the Convair 880 by the big lumps on the trailing edge.
The Trident was also very quick but the Comet was only a .72/.75 airplane

[quid]

Here we go again......

[Tim Zukas]

www.airliners.net/discussions/tech_ops/read.main/10012/ (http://www.airliners.net/discussions/tech_ops/read.main/10012/)

[Speedbird48]

It was the Convair 990, Coronado. Spantax were the last operator and Nasa had one for a while.
The Trident was also very fast but the Comet was only a .72/.75 airplane.

[Pdub]

Oh no, off we go again..... <hides head in hands, while putting on Spantex trousers :) >

[wrecker]

The Trident 1 had a M.88 cruise with a Vmo of 385 We used to demonstrate them during Base Flying to M.93 as required by the 1179 form. I have seen them at M.97 with no mach buffet until some G pulled and then only very slight. I remember a time when we were hasseled by a pair of Spanish F86s after departing from Gibralter and managed to pull away from them at m.9+

[jtr]

I seem to remember someone once saying that it was the Convair 990. The Trident was also very fast but the Comet was only a .72/.75 airplane.
LMAO

[BEagle]

What was the burn rate of a Trident 1 at M.93? Could it sustain a cruise at M.93 for any length of time, or was that only in a descent?

Would make a pretty quick short range transport toy for a rich businessman these days, perhaps? Especially with modern engines?

[Trident Sim]

BEagle

I don't know which airline wrecker flew with, nor which mark of Trident, although the reference to Gibraltar suggests it may have been BEA.

If it was BEA, talk of a M0.88 cruise and a Vmo of 385 kts for a Trident 1 is somewhat over the top!

For the record all the Tridents in BEA/BA had an Mmo of M0.87, with the Tridents 1 & 2 having a Vmo of 365 kts (300 kts for a Trident 2 with fuel in the fin tank) and the Trident 3 having a Vmo of 350 kts.

M0.93 may have been demonstrated at base, but was way above the normal cruise mach number.

[BEagle]

Thanks - I did wonder as I thought that those IMN figures seemed on the high side! Until the Fun Detectors stopped us, we used to cruise the Vickers Funbus at M0.88 indicated; however, I still have to take her over M0.92 on air tests. A little buffet sets in at that speed, but otherwise the old lady handles it without any drama!

[This message has been edited by BEagle (edited 03 March 2001).]

[Jim lovell]

The Trident was very fast but the Comet was only a .72/.75 airplane

LMAO

What about the 757- close to M .9?

[gaunty]

Pdub
you do look georgeous in your Spantax trousers.

The Trident was also very quick but the Comet was only a .72/.75 airplane.

I did have the pleasure of a Spantax CV990 but can honestly say that the clouds did not seem to be going backwards any faster. :)

[Speedbird48]

It was the Convair 990 Coronado last flown by Spantax and NASA had one for a while. It could be separated from the 880 by the big fairings on the wing trailing edge.
The Trident was also fast but the Comet was only a .72/.75 airplane. Ah, De-Havilland!!

[Tobbes]

Understand that the last flying CV-990 was used by the US Navy as a trials a/c, and at least one piccie exists of it with an AAR pod fitted -- believe that it was flying into the 1990s. Does anyone have anymore information?

Tobbes

(Oh and the Comet might have been a .72/.75 aeroplane. : ) !)

[This message has been edited by Tobbes (edited 08 March 2001).]

[Smoketoomuch]

Speedbird48,

Do you talk in your sleep? I wonder what you say... :)