bananaboy
Topic Author
Posts: 1636
Joined: Wed Oct 20, 2004 6:58 am

Tristar Nose-up On Landing

Thu Dec 16, 2004 5:34 am

Is it my imagination or does / did the Tristar seem to fly its approach with its nose pointing up quite a bit?

Looking at the photos in the database, and from memory of having flown on one a couple of times, it seems as though this is the case. In fact, I remember it being quite noticeable on the couple of occasions that I did fly on one.

Is this deliberate? How much more of an angle do they point up that similar aircraft, say the DC10? Why? (although I am guessing this reduces the actual landing speed of the aircraft)

Or perhaps I don't have a clue what I am talking about! hahaha  Laugh out loud


Mark
All my life, I've been kissing, your top lip 'cause your bottom one's missing
 
corey07850
Posts: 2335
Joined: Wed Feb 04, 2004 4:33 am

RE: Tristar Nose-up On Landing

Thu Dec 16, 2004 5:43 am

I believe this is normal for most (if not all) aircraft that have leading edge slats on the wings. The way the air flows over/through the wing and slats tends to lead to a nose-up attitude during approach...
 
Newark777
Posts: 8283
Joined: Thu Dec 02, 2004 6:23 am

RE: Tristar Nose-up On Landing

Thu Dec 16, 2004 6:25 am

But don't most modern jetliners have leading edge slats? Or do they just not use them on approach? If this nose-up attitude was caused by the slats, wouldn't all jets have this same characteristic, and not just the tristars?
Why grab a Heine when you can grab a Busch?
 
DBCooper
Posts: 178
Joined: Wed Jun 16, 2004 2:51 am

RE: Tristar Nose-up On Landing

Thu Dec 16, 2004 7:54 am

Early series DC-9s (-10/14/15) and F-100s do not have leading edge slats.

I don't recall EMB-RJs having them either, for that matter.


- DBC
 
corey07850
Posts: 2335
Joined: Wed Feb 04, 2004 4:33 am

RE: Tristar Nose-up On Landing

Thu Dec 16, 2004 8:24 am

If you notice, it's not only tri-stars that have nose-up approaches...


View Large View Medium
Click here for bigger photo!

Photo © Carlo Dal Bianco
View Large View Medium
Click here for bigger photo!

Photo © John E. Jauchler





View Large View Medium
Click here for bigger photo!

Photo © Mark Sluiters
View Large View Medium
Click here for bigger photo!

Photo © Charles Falk



I've noticed that the DC-9/MD-80 series aircraft seem to constantly have a pronounced nose-up attitude on approach.
 
bananaboy
Topic Author
Posts: 1636
Joined: Wed Oct 20, 2004 6:58 am

RE: Tristar Nose-up On Landing

Thu Dec 16, 2004 8:34 am

Hmmm. Maybe its just me then...


I am sure I read / heard somewhere that the TriStars angle of attack on approach was greater than the majority of civil airliner, and that they almost had a "reputation" for their unique "profile" on approach.

I realise though, that it is not the only one to do this...


Mark
All my life, I've been kissing, your top lip 'cause your bottom one's missing
 
OldAeroGuy
Posts: 3886
Joined: Sun Dec 05, 2004 6:50 am

RE: Tristar Nose-up On Landing

Thu Dec 16, 2004 10:25 am

The L1011 employed direct lift control on approach. This was done by raising the spoilers slightly, which required that the angle of attack be increased to maintain the same lift at a given airspeed. Spoiler angle could than be varied to control the airplane relative to the glideslope.

If the airplane was below the glideslope, a reduction in spoiler deflection would increase lift and cause the airplane to climb.

If the airplane was above the glideslope, the spoiler angle would be increased, lowering lift and causing the airplane to descend.

Use of an autothrottle to hold speed freed the pilot from the need to adjust power to compensate for the drag changes caused by changing spoiler angle.

I'm not sure how the flight controls behaved in this situation, but I believe direct lift control was only active at landing flap and that small column movements controlled the necessary spoiler deflections.

The advantage of direct lift control is that the approach could be flown at constant body attitude, with spoiler angle changes rather than airplane pitch changes being used to track the glideslope.

Why isn't direct lift control used today? The L1011 was designed before the current noise rules were put into effect. Opening the spoilers increases drag and engine thrust increases to compensate, creating more approach noise. Current noise rules require low drag on approach, which is one of the reasons you don't see triple slotted flaps on newly designed airliners.
Airplane design is easy, the difficulty is getting them to fly - Barnes Wallis
 
411A
Posts: 1788
Joined: Mon Nov 12, 2001 10:34 am

RE: Tristar Nose-up On Landing

Thu Dec 16, 2004 12:19 pm

OldAeroGuy had indeed described the direct lift control used on the TriStar, rather accurately.
The TriStar, at all landing weights, maintained a 7.5 degree (approximately) nose up attitude on approach.
The DLC system is very accurate, and enabled CATIIIB certification easily.
In addition, the TriStar was stage III noise compliant, at all weights.

The only other 'aircraft' that uses direct lift control on approach is the Space Shuttle, and indeed, in the early days, shuttle astronauts trained on the Delta L1011 sim.

The TriStar is a truly superb aircraft, and I was pleased to have flown it for twenty years.
 
User avatar
TZTriStar500
Posts: 891
Joined: Sat Jan 03, 2004 1:33 am

RE: Tristar Nose-up On Landing

Sun Dec 19, 2004 12:41 pm

Damn! This aircraft never ceases to amaze me in its design! I provide engineering support for the 5 TriStars that we have left at ATA and the more I learn about its systems, the more I am impressed on the incredibly advanced design for its time.

Other features such as the flying tail(horizontal stab), the Active Control System(ACS) for the -500 aileron system, autothrottles, and Autoland come to mind. In fact Lockheed has a patent on the term "Autoland" since it was the first commercial airliner to have it.

Other than its obvious age, this aircraft in many ways is just as advanced as those aircraft being built today. Very impressive for a design thats over 30 years old!

To bad the TriStar will soon depart from the world scene for good :-(
35 years of American Trans Air/ATA Airlines, 1973-2008. A great little airline that will not be soon forgotten.
 
spencer
Posts: 1518
Joined: Sun Apr 25, 2004 8:30 pm

RE: Tristar Nose-up On Landing

Sun Dec 19, 2004 9:51 pm

Wasn't the HS121 Trident first to use Autoland?
Spencer.
EOS1D4, 7D, 30D, 100-400/4.5-5.6 L IS USM, 70-200/2.8 L IS2 USM, 17-40 f4 L USM, 24-105 f4 L IS USM, 85 f1.8 USM
 
411A
Posts: 1788
Joined: Mon Nov 12, 2001 10:34 am

RE: Tristar Nose-up On Landing

Mon Dec 20, 2004 6:20 am

The first civil type...yes.
However the very first type (properly certified for use) was the Shorts SC.3 Belfast, for the Royal Air Force.
During trials, the glidepath at the airfield under use had to be electronically shifted halfweay thru the trials, due to the aircraft landing PRECISELY at the same spot...with the resultant runway surface deterioration.

Both, you will note, were British designs.

Then, when the Lockheed folks wanted an autopilot system as accurate as the Trident, they directly hired some of the 'ole Smiths group, that developed the superb Trident triplex autopilot system, to design same for the big Lockheed tri-motor....and these folks did a superb job.

Nothing finer...IMO.
 
User avatar
winterlight
Posts: 1432
Joined: Wed Oct 29, 2014 8:57 am

RE: Tristar Nose-up On Landing

Sat Feb 27, 2016 7:41 pm

So the ol' Trident and Tristar were alike in more ways than one.
Question everything. Trust no-one.
 
User avatar
DocLightning
Posts: 21591
Joined: Wed Nov 16, 2005 8:51 am

RE: Tristar Nose-up On Landing

Sat Feb 27, 2016 9:54 pm

Quoting OldAeroGuy (Reply 6):

I'm not sure how the flight controls behaved in this situation, but I believe direct lift control was only active at landing flap and that small column movements controlled the necessary spoiler deflections.

The advantage of direct lift control is that the approach could be flown at constant body attitude, with spoiler angle changes rather than airplane pitch changes being used to track the glideslope.

Given that this was all achieved in an aircraft that was not FBW, how did Lockheed design the controls so as to activate DLC? Since pilots loved DLC so much, why has it not been reinstated on FBW aircraft? Surely this would be well within the capabilities of any major OEM that has ever used FBW.
-Doc Lightning-

"The sky calls to us. If we do not destroy ourselves, we will one day venture to the stars."
-Carl Sagan
 
User avatar
TupolevTu154
Posts: 1926
Joined: Fri Aug 27, 2004 6:00 pm

RE: Tristar Nose-up On Landing

Sat Feb 27, 2016 11:54 pm

Quoting winterlight (Reply 11):

So the ol' Trident and Tristar were alike in more ways than one.

You deserve some sort of award for bumping a thread from 11 years ago. How on earth did you find this?! Good effort!
 
Max Q
Posts: 7809
Joined: Wed May 09, 2001 12:40 pm

RE: Tristar Nose-up On Landing

Sun Feb 28, 2016 5:04 am

Quoting DocLightning (Reply 12):
why has it not been reinstated on FBW aircraft?

I believe a form of it has been, in the modified control system on, for example the A318 and
other FBW types that operate into London City Airport.


In order to fly the very steep glide slope, not accelerate and keep engines spooled the
spoilers are deployed and varied in deflection on approach in a somewhat similar
manner to the superb L1011.


For a moment I though someone had resurrected dear old 411A !


RIP.
The best contribution to safety is a competent Pilot.


Guns are a malignant cancer that are destroying our society
 
BoeingGuy
Posts: 6314
Joined: Fri Dec 10, 2010 6:01 pm

RE: Tristar Nose-up On Landing

Sun Feb 28, 2016 7:26 am

Quoting TZTriStar500 (Reply 8):
In fact Lockheed has a patent on the term "Autoland" since it was the first commercial airliner to have it.

I'd always heard the Trident was first, although somewhere I read the DC-8 also could autoland.

Didn't they try automatic takeoffs with the L-1011, which are not prohibited for any airplane?
 
Pihero
Posts: 4318
Joined: Mon Jan 31, 2005 5:11 am

RE: Tristar Nose-up On Landing

Sun Feb 28, 2016 2:15 pm

Quoting OldAeroGuy (Reply 6):
The L1011 employed direct lift control on approach. This was done by raising the spoilers slightly

Yes, spoilers 1 to 4 - on each wing - by some 7° and then, for DLC, they coud be moved 7° either side of that initial setting. ( so their range would be 0° to 14° )

Quoting OldAeroGuy (Reply 6):
If the airplane was below the glideslope, a reduction in spoiler deflection would increase lift and cause the airplane to climb.

Not a *climb* per se, just a reduction of the descent rate.

Quoting OldAeroGuy (Reply 6):
Use of an autothrottle to hold speed freed the pilot from the need to adjust power to compensate for the drag changes caused by changing spoiler angle.

No. manually flying the Tristar was a joy, especially when the DLC, as a matter of fact was enhancing the pitch / speed and throttle / path piloting philosophy.
JUst nail that aiming point of yours to the windscreen.

Quoting OldAeroGuy (Reply 6):

Why isn't direct lift control used today?

You describe the first reasons : noise. But with a sngle-slotted flap config and our nowadays's engines, it shouldn't be a problem.
The reason has a lot more to do with simplicity, because implementing the DLC / AGS on the Tristar was nothing short of miraculous : One could spend months just studying the FCES and the spoiler mixer.
Just as an example, in the approach, spoilers 2 to 6 are also available for roll control ; This means that 40° of roll inputs can be applied to spoilers 2 through 4, adding to the DLC range., hence to a maximum deflection of 54°.
One of the greatest corollaries of that set up was that, at Go-Around, the DELC spoilers would retract, causing an immediate increase in lift ( I was told of about 10 tons ) and an immediate climb. Even at a 15 ft radio height, you wouldn't touch-down, contrarily to all other airliners

Quoting Spencer (Reply 9):
Wasn't the HS121 Trident first to use Autoland?

NO !
By a lot of measures, that belongs to the Caravelle :
It made the first automated landing in September 1962.
It was certified for automatic landing in normal OPS in 1963
It was the first aircraft certified for Cat II landing in September 1964., the full landing wasn't yet authorised for passenger service, but only for training.
- The first fully automated landings in passenger service belong to the BEA Tridents on 10th June 1965. ( but in CAVOK conditions )
First aircraft certified for Cat III A : Caravelle on 2nd March 1967
First fully automated landing in Cat III A conditions on 9th January 1969, and repeated on the same day 8 times by different aircraft. (The BEA Tridents achieved the same certification[b] in 1972, [b]five years behind the Air Inter Caravelles.
The Tristar joined that club in 1974, but after the Bac 1-11 and the Mercure ( which was the first airliner with a HUD)

Quoting BoeingGuy (Reply 15):
I'd always heard the Trident was first, although somewhere I read the DC-8 also could autoland.

The first airliner to be so certified by the FAA, big difference as the FAA did not believe in Cat III. I have a British friend who used to fly the Trident and was really p***ed off when transferred to the newest fleet addition : the 757 did not have the Trident capability -initially, I think.

The DC-8 couldn't do it.

Quoting Max Q (Reply 14):

I believe a form of it has been, in the modified control system on, for example the A318 and
other FBW types that operate into London City Airport.


The Lockheed DLC / AGS as a precursor to the A318 SAC ?
I don't think so : The SAC is just a way to increase the A318 drag, allowing a 5.56° glide slope... No pitch influence... some spoilker range increase for roll control... Nah ! the 1011 DLC was a lot more advanced.
- There is no other LCY- capable 100 seater .

As we are on the subject of the Tristar, Max would love the fact that it doesn't have a manual reversion : all hydraulics gone, down it goes !... but it didn't : the redundancies and system safety introduced by Lockheed were extraordinary.
Duiring certification, the airplace was deemed to be the safest airliner ever in case of multiple / multiple failures.
Contrail designer
 
Tristarsteve
Posts: 3601
Joined: Tue Nov 22, 2005 11:04 pm

RE: Tristar Nose-up On Landing

Sun Feb 28, 2016 4:21 pm

Quoting BoeingGuy (Reply 15):
Didn't they try automatic takeoffs with the L-1011

Don't think so. But the Tristar in BA service was equipped with the same barbers pole device on the glareshield that was a direct copy from the item installed on the Trident. This was driven by the Localisor signal and provided steering advice to the pilot during a low visibilty take off, as well as after touchdown. This allowed take off in Cat 111 conditions.

We used to refuel LTU Tristars in Bahrain. They were flying MLE-BAH-DUS with one crew, and they stopped for fuel only for about 20 mins in BAH due crew hours!
They always landed with the nose pointed skywards, and then rolled along the runway like that, which left the brakes cold when they got on the gate.
 
Pihero
Posts: 4318
Joined: Mon Jan 31, 2005 5:11 am

RE: Tristar Nose-up On Landing

Sun Feb 28, 2016 6:12 pm

Quoting Tristarsteve (Reply 17):
the Tristar in BA service was equipped with the same barbers pole device on the glareshield that was a direct copy from the item installed on the Trident.

You're describing the PVD aka *para visual display*, used always with the GRM - Ground Run Monitor - for LVP take offs.
The GRM was disabled in 1984 IIRC.

Quoting Tristarsteve (Reply 17):
They always landed with the nose pointed skywards, and then rolled along the runway like that

You are pointing at the only wekness of the 1011 : those pesky steel brakes, so quick to rise in temperature. The technique you describe was the choice of a lot of aircrews : the idea was never to apply the brakes over 80 kt, unless one was pushed to use them earlier ( runway end coming quick ! ).
Contrail designer
 
Max Q
Posts: 7809
Joined: Wed May 09, 2001 12:40 pm

RE: Tristar Nose-up On Landing

Sun Feb 28, 2016 11:06 pm

Quoting Pihero (Reply 16):

I don't think so : The SAC is just a way to increase the A318 drag, allowing a 5.56° glide slope... No pitch influence... some spoilker range increase for roll control... Nah ! the 1011 DLC was a lot more advanced.
- There is no other LCY- capable 100 seater .

Outboard spoilers are deflected to provide more drag on approach, not really the same set up as the Tristar but it does
have some of the same effect.

Quoting Pihero (Reply 16):
As we are on the subject of the Tristar, Max would love the fact that it doesn't have a manual reversion : all hydraulics gone, down it goes !... but it didn't : the redundancies and system safety introduced by Lockheed were extraordinary.
Duiring certification, the airplace was deemed to be the safest airliner ever in case of multiple / multiple failures.

No widebody aircraft have manual reversion, i'm sure you know that, the forces involved would simply be too great
to provide for it.


But the Tristars superb safety record speaks for itself, it was a great aircraft, in contrast to the DC10.
The best contribution to safety is a competent Pilot.


Guns are a malignant cancer that are destroying our society
 
BoeingGuy
Posts: 6314
Joined: Fri Dec 10, 2010 6:01 pm

RE: Tristar Nose-up On Landing

Mon Feb 29, 2016 12:12 am

Quoting Tristarsteve (Reply 17):
Don't think so. But the Tristar in BA service was equipped with the same barbers pole device on the glareshield that was a direct copy from the item installed on the Trident. This was driven by the Localisor signal and provided steering advice to the pilot during a low visibilty take off, as well as after touchdown. This allowed take off in Cat 111 conditions.

BA's 777s, 767s, and 747s have PVDs too. I believe the SW MD-11s had them also.
 
BoeingGuy
Posts: 6314
Joined: Fri Dec 10, 2010 6:01 pm

RE: Tristar Nose-up On Landing

Mon Feb 29, 2016 12:14 am

Quoting Pihero (Reply 16):
Quoting BoeingGuy (Reply 15):
I'd always heard the Trident was first, although somewhere I read the DC-8 also could autoland.

The first airliner to be so certified by the FAA, big difference as the FAA did not believe in Cat III. I have a British friend who used to fly the Trident and was really p***ed off when transferred to the newest fleet addition : the 757 did not have the Trident capability -initially, I think.

The 757 was Cat 3B triple channel autoland certified out the box at delivery for as long as I can remember. Maybe that wasn't true initially - I'm not sure - but it was that way for at least most of the life of the airplane.
 
Viscount724
Posts: 19316
Joined: Thu Oct 12, 2006 7:32 pm

RE: Tristar Nose-up On Landing

Mon Feb 29, 2016 3:07 am

Quoting TupolevTu154 (Reply 13):
Quoting winterlight (Reply 11):

So the ol' Trident and Tristar were alike in more ways than one.

You deserve some sort of award for bumping a thread from 11 years ago. How on earth did you find this?!

I wish people that resurrect old threads like this would mention it in their first reply so you don't start reading the entire thread before noticing it's 12 years old. I also have no idea how people find such old threads since the A.net search function is so bad. Half the time you can't even find a thread from last week (searching in Google works much better, limiting results to the airliners.net site).

Re the subject of the thread, I recall comments from L-1011 cabin crew that even at cruise altitude it had a more pronounced nose-up attitude than many other aircraft, requiring more effort to push meal trolleys "uphill". It was also somewhat noticeable as a passenger.
 
User avatar
DocLightning
Posts: 21591
Joined: Wed Nov 16, 2005 8:51 am

RE: Tristar Nose-up On Landing

Mon Feb 29, 2016 4:24 am

Quoting Max Q (Reply 19):

But the Tristars superb safety record speaks for itself, it was a great aircraft, in contrast to the DC10.

From the point of view of systems and overall quality of engineering, yes. Passengers liked it, pilots liked it, crew liked it. Airlines...not so much.

The squatter stance and the position of the #2 engine within the tailcone proper meant that installing larger-diameter, more powerful engines was almost impossible. While the nacelles on the DC-10 could be expanded a bit to make it fly farther with the -40 series, this sort of change could not be done for the L-1011 without redesigning the entire tail.

The DC-10 went on to enjoy a long and successful career as the main "smaller widebody" and an alternative to the 747 for airlines that did not want an airplane as big as the 747. While the A330 and A340 at first encroached on the DC-10, the MD-11 remained an alternative for airlines that wanted reliable transpacific range but not something the size of a 747. Had the MD-11 actually performed on target, maybe more would have been built. But the real DC-10 replacement was the 772.

The L-1011 replacement was...the DC-10.  
-Doc Lightning-

"The sky calls to us. If we do not destroy ourselves, we will one day venture to the stars."
-Carl Sagan
 
Max Q
Posts: 7809
Joined: Wed May 09, 2001 12:40 pm

RE: Tristar Nose-up On Landing

Mon Feb 29, 2016 4:41 am

Not really, most long term L1011 operators with the exception of Hawaian replaced their Tristars with other
types such as the 767-400 even the 777 A models.


The DC10 may have sold a few more but it had an atrocious safety record compared to the Tristar which
never had a design caused accident.
The best contribution to safety is a competent Pilot.


Guns are a malignant cancer that are destroying our society
 
Viscount724
Posts: 19316
Joined: Thu Oct 12, 2006 7:32 pm

RE: Tristar Nose-up On Landing

Mon Feb 29, 2016 5:12 am

Quoting Max Q (Reply 24):
The DC10 may have sold a few more

A few more? 54% more (386 vs. 250) if you don't count the 60 KC-10 tankers, and 78% more (446 vs. 250) if you do. That's more than a few.

And the DC-10 didn't bankrupt McDonnell Douglas, unlike the L-1011 which almost bankrupted Lockheed and required a US government bailout, and did bankrupt Rolls-Royce due to RB211 engine development issues and forced the British government to nationalize Rolls-Royce for the next 16 years or so.
 
Pihero
Posts: 4318
Joined: Mon Jan 31, 2005 5:11 am

RE: Tristar Nose-up On Landing

Mon Feb 29, 2016 8:42 pm

Quoting DocLightning (Reply 23):
The L-1011 replacement was...the DC-10.

While I could understand the joke, that is not correct : one's replacement should both be newer and better... which the DC-10 never was.
What killed the 1011, and indeed the DC-10 was the new big twins, the first being the 763 ( ER)... I, remember very well t-alking to the pîlots who evaluated the 76 for my airline : He said :" Total fuel flows are exactly the same... but the 76's was in pounds and the Tristar in kilos"

Quoting Viscount724 (Reply 25):
And the DC-10 didn't bankrupt McDonnell Douglas

Sorry . My measures of a good airplane ,are more about human lives lost... That makes the -10 the worst widebody ever. ( BTW : I was known to be one of those who refused a DC-10 rating as it would have been akin to going to a far lower class
of airplane... I went instead to the 747 with some loss of seniority ( didn't bother me ) )

Quoting Viscount724 (Reply 22):
I recall comments from L-1011 cabin crew that even at cruise altitude it had a more pronounced nose-up attitude than many other aircraft

The Tristar was cloisely tailored for the fastest cruise then available : > .85 M, at which it was horizontal ( 0° pitch )
Looking for long range, then you'd have 4 to 5° nose up.
That is in fact the case for all airplanes, more noticeable on the -1011 because of the long, uninterrupted cabins of trhe likes of CourtLine .
I captained the 1011 for nearly seven years without ever a complaint from the cabin crews on that respect.
Contrail designer
 
User avatar
DL_Mech
Posts: 2344
Joined: Fri Feb 18, 2000 7:48 am

RE: Tristar Nose-up On Landing

Mon Feb 29, 2016 10:52 pm

Quoting Pihero (Reply 26):
The Tristar was cloisely tailored for the fastest cruise then available : > .85 M, at which it was horizontal ( 0° pitch )
Looking for long range, then you'd have 4 to 5° nose up.


I was told the same thing by a Lockheed engineer. Once the airlines slowed the airplane down, it flew with the "nose up" attitude at cruise.
This plane is built to withstand anything... except a bad pilot.
 
vc10
Posts: 1412
Joined: Thu Nov 15, 2001 4:13 am

RE: Tristar Nose-up On Landing

Thu Mar 03, 2016 1:57 pm

Quoting Viscount724 (Reply 25):
A few more? 54% more (386 vs. 250) if you don't count the 60 KC-10 tankers, and 78% more (446 vs. 250) if you do. That's more than a few.

And the DC-10 didn't bankrupt McDonnell Douglas, unlike the L-1011 which almost bankrupted Lockheed and required a US government bailout, and did bankrupt Rolls-Royce due to RB211 engine development issues and forced the British government to nationalize Rolls-Royce for the next 16 years or so.

Slightly off topic, but in response to the above , could the comparison be made to Douglas and Lockheed design teams with the DC4 to 7 series and the Constellation design

The Douglas were relatively simple and used trusted knowledge in both airframe and engines [ well until the DC-7C ]
The Constellation was perhaps more state of the art in both airframe and engines , but was somewhat more unreliable and more expensive to maintain .

Perhaps the two companies design thinking carried on into the Tri-star and DC-10 designs

littlevc10
 
Pihero
Posts: 4318
Joined: Mon Jan 31, 2005 5:11 am

RE: Tristar Nose-up On Landing

Thu Mar 03, 2016 6:24 pm

Let's start from the beginning :

Quoting Viscount724 (Reply 25):
And the DC-10 didn't bankrupt McDonnell Douglas, unlike the L-1011 which almost bankrupted Lockheed and required a US government bailout

One could putt all the blame right on RR's lap : Over-promises on the RB-211 ( the fan blades as the best instance )...
RR went bankrupt.
At that point, it was too late to change the engine choice, the redesign would have cost another fortune.
Bail out ? No ! The Brits would re-finance and re-launch the RB-211 and would require from the US government a guarantee that Lockheed would really pay for the engines it buys... basically Lockheed became - that's really not well known - a government-owned manufacturer during the L-1011 production.

Quoting vc10 (Reply 28):
The Douglas were relatively simple and used trusted knowledge in both airframe and engines ...
The Constellation was perhaps more state of the art in both airframe and engines , but was somewhat more unreliable and more expensive to maintain .

I disagree : Both manufacturers kept a constant evolution on their products :
-For Douglas it was the DC-4 followed by the DC-6, the DC-7 and the DC-7C Seven Seas
- For Lockheed, it was the Constellation,... then the Super-Constellation, ending with the Starliner.
The problem was that right from the beginning, the Lockheed product was far superior, with quite a few technological firsts for transport aircraft : hydraulic flight controls, air conditioned cabin, pressurised cabin,...etc...
Of course, it was more expensive
- to build with that porpoise fuselage shape vs the simplicity of a constant diameter barrel. ( The legend says Howard Hugues insisted on keeping that beautiful shape )...
- to maintain : up until the 7C included all these feature's AND used the same engines, at which point there was basically no difference.

In my opinion, the DC-10 was too hastily designed and built with a lot of tech loopholes which revealed themselves at a very high human cost : the cargo doors design / the absence of hydraulic plugs on the hydraulic system (along with it's basic lack of redundancy) / the badly designed flight control ( cable runs / spoilers which when deployed caused a phenomenal poitch-up moment....)
The L-1011 was light years more advanced, and for a start, the whole architecture was built around a modular instrument and navigatioin system ( called MONA).

Finally, may I just remind you that using simple and used trusted knowledge for their product evolution is what killed Douglas : I personally saw the writings on the wall when I tested the MD-80 and then the A320 in 1988...
Contrail designer
 
User avatar
readytotaxi
Posts: 6712
Joined: Mon Dec 11, 2006 2:09 am

RE: Tristar Nose-up On Landing

Fri Mar 04, 2016 7:51 pm

What a wonderful thread this is, so much information about a sadly missed aircraft.   
you don't get a second chance to make a first impression!
Growing older, but not up.
 
badgervor
Posts: 139
Joined: Sun Apr 13, 2014 10:58 pm

RE: Tristar Nose-up On Landing

Fri Mar 04, 2016 9:43 pm

 
Viscount724
Posts: 19316
Joined: Thu Oct 12, 2006 7:32 pm

RE: Tristar Nose-up On Landing

Sat Mar 05, 2016 4:13 am

Quoting Pihero (Reply 29):
Quoting vc10 (Reply 28):
The Douglas were relatively simple and used trusted knowledge in both airframe and engines ...
The Constellation was perhaps more state of the art in both airframe and engines , but was somewhat more unreliable and more expensive to maintain .

I disagree : Both manufacturers kept a constant evolution on their products :
-For Douglas it was the DC-4 followed by the DC-6, the DC-7 and the DC-7C Seven Seas
- For Lockheed, it was the Constellation,... then the Super-Constellation, ending with the Starliner.

It didn't help that the L-1649A Starliner was a year later than the DC-7C going into service, by which time virtually nobody was interested in longhaul props with jets on the horizon. Also, Lockheed never had an aircraft with the performance and economics of the DC-6B, probably the most reliable, profitable and versatile 4-engine piston airliner ever built. The P&W R2800 engines were a big factor as they were much more reliable than the Wright 3350 on all Constellation models (and DC-7). That's one reason why DC-7s had a much shorter lifespan after their mainline days were over while some DC-6Bs are still flying today.
 
bananaboy
Topic Author
Posts: 1636
Joined: Wed Oct 20, 2004 6:58 am

RE: Tristar Nose-up On Landing

Sat Mar 05, 2016 8:24 am

Wow.. had forgotten all about this thread.

My favourite aircraft..   

So, as per the prior responses, DLC means that the pitch of the aircraft is locked and the spoilers are deployed to help track the glideslope as far as I understand.

What I didn't see answered is what is the pitch up attitude? How many degrees? Is it possible to say that the L1011 had a greater nose-up pitch on approach than other aircraft. I know that many aircraft will be nose-up on approach.. it's whether the L1011 is more-so than most others?

Thanks

Mark
All my life, I've been kissing, your top lip 'cause your bottom one's missing
 
Pihero
Posts: 4318
Joined: Mon Jan 31, 2005 5:11 am

RE: Tristar Nose-up On Landing

Sat Mar 05, 2016 1:57 pm

Quoting bananaboy (Reply 33):
DLC means that the pitch of the aircraft is locked

No ; don't go to extremes : pitch control through the elevator is still available, but only after you've reached the DLC limits on the spoilers.
The characteristic which used to take some serious thinking about : on a visual approach, one had to concentrate a lot on the *geometry* of the approach in the windscreen instead of the pitch variations : the DLC will not change the aspect of the horizon..........until you find yourself too high or too low, and drastically so !
The correction needed to be both smooth and deliberate : get that aiming point where it should be on the glareshield !

Quoting bananaboy (Reply 33):
what is the pitch up attitude?

Around 3 to 4° nose up on glide slope. That's about 1.5 to 2° higher than on *normal* airplanes.

Quoting bananaboy (Reply 33):
the L1011 is more-so than most others?

You could say that, yes.

Quoting Viscount724 (Reply 32):
some DC-6Bs are still flying today.

The 3350 needed some serious maintenance capabilities. The double Wasp was just about an evolution of the Twin Wasp on the DC-4. These engines were known for their toughness and reliability.
I flew both... I loved the DC-4 and not so much the -6 for its heavy controls and noise in the cockpit.
Contrail designer
 
BravoOne
Posts: 3686
Joined: Fri Apr 12, 2013 2:27 pm

RE: Tristar Nose-up On Landing

Sat Mar 05, 2016 4:22 pm

Quoting Pihero (Reply 34):
I loved the DC-4 and not so much the -6 for its heavy controls and noise in the cockpit.

Can you expand on that? I also flew the DC4, DC6B, DC7C and the L1049H and can't recall what any of these sounded like now 
 
Pihero
Posts: 4318
Joined: Mon Jan 31, 2005 5:11 am

RE: Tristar Nose-up On Landing

Sat Mar 05, 2016 10:38 pm

Quoting BravoOne (Reply 35):
DC7C and the L1049H

Bloody Hell ! I'm so jealous : you flew the aircraft I've been in love with since I was eight : THE Connie !
The DC-6 was quite a lot noisier than the -4, with a higher pitch, while the DC-4 had a very comfortable - comforting drone.
Piloting-wise, the feel of the flight controls was heavier, a bit sluggish even, although everything came back nicely at approach speeds... Mind you I have thousands of hours on the -4 and just about 150 on the -6...so I could be a bit partial. The DC-4 was a child's dream come true, whereas the -6 was *just another plane* which did not impress me at all (apart from its performances ) I was glad to fly back the DC-4 for another year before going to jets ( at which point I missed the comfort of its droning noise !

[Edited 2016-03-05 14:40:18]
Contrail designer
 
Aircellist
Posts: 1530
Joined: Fri Oct 08, 2004 8:43 am

RE: Tristar Nose-up On Landing

Sun Mar 06, 2016 2:22 am

Quoting Pihero (Reply 36):

Have you started writing your memoirs? I'd purchase them even from a subscription (esp. if they were written in French   )
"When I find out I was wrong, I change my mind. What do you do?" -attributed to John Maynard Keynes
 
Max Q
Posts: 7809
Joined: Wed May 09, 2001 12:40 pm

RE: Tristar Nose-up On Landing

Sun Mar 06, 2016 5:27 am

Quoting Aircellist (Reply 37):
Have you started writing your memoirs? I'd purchase them even from a subscription

I think that would be a very interesting book, we need an English version though !
The best contribution to safety is a competent Pilot.


Guns are a malignant cancer that are destroying our society
 
bananaboy
Topic Author
Posts: 1636
Joined: Wed Oct 20, 2004 6:58 am

RE: Tristar Nose-up On Landing

Sun Mar 06, 2016 5:33 am

Pihero, awesome answer. Thank you.

Mark
All my life, I've been kissing, your top lip 'cause your bottom one's missing
 
BravoOne
Posts: 3686
Joined: Fri Apr 12, 2013 2:27 pm

RE: Tristar Nose-up On Landing

Sun Mar 06, 2016 4:13 pm

Well my time in the DC4 and Carvair was all in the Congo (1963) and it was the 1st big airplane I had ever flown at the time. Don't recall if it was noisy or not as I was just hanging on for dear life and most of the Capt were not using English as their 1st language either, O the other hand the DC6B was pressurized, air conditioned (of sorts), and we flew it at pretty low power settings, as in low blower all the time,
The L1049H were mostly freighters and probably had little sound insulation aft of the flight deck so know telling how much noise got through? Flew the L188 Electra for a awhile and found it to be a very nice airplane 
 
BoeingGuy
Posts: 6314
Joined: Fri Dec 10, 2010 6:01 pm

RE: Tristar Nose-up On Landing

Mon Mar 07, 2016 12:24 am

Quoting Pihero (Reply 34):
Quoting bananaboy (Reply 33):
DLC means that the pitch of the aircraft is locked

No ; don't go to extremes : pitch control through the elevator is still available, but only after you've reached the DLC limits on the spoilers.

Did DLC work even if you are flying the glideslope manually? Where the stick inputs translated into spoiler deflections, if you were below DLC limits?

What if you are hand flying a visual approach? Then was it standard elevator inputs?

I agree the L-1011 was a fascinating airplane. I like the PSA L-1011s the best. Too bad that was an economic disaster, but the Mother Grinningbirds sure were beautiful.
 
PGNCS
Posts: 2257
Joined: Sun Apr 15, 2007 5:07 am

RE: Tristar Nose-up On Landing

Mon Mar 07, 2016 1:53 am

Quoting BoeingGuy (Reply 41):
Did DLC work even if you are flying the glideslope manually?

Yes, as long as the flaps were in 33 (or 42).

Quoting BoeingGuy (Reply 41):
here the stick inputs translated into spoiler deflections, if you were below DLC limits?

Don't understand your question here. Are you asking about being low on the glideslope? In that case the DLC spoilers would progressively close until they were flush with the wings as you pulled back on the yoke (less drag=climb); further pitch control moved the entire stabilator, which was VERY effective.

Quoting BoeingGuy (Reply 41):
What if you are hand flying a visual approach? Then was it standard elevator inputs?

No. DLC is a function of being in the landing flap setting, not what kind of approach you are flying or what level of automation you are using. It is pure genius.
 
Pihero
Posts: 4318
Joined: Mon Jan 31, 2005 5:11 am

RE: Tristar Nose-up On Landing

Mon Mar 07, 2016 5:34 am

Hi, PGNCS ! Long time no read !

Quoting PGNCS (Reply 42):
It is pure genius.

For the crews flying her, in fact they all agreed that she was "PURE F...ING MAGIC"

Quoting Aircellist (Reply 37):
Have you started writing
Quoting Max Q (Reply 38):
Quoting Aircellist (Reply 37):

I've started jotting notes... It will be quicker if I had decided on the format : don't want memoirs / not decided on a novel... I think it will be about dream of flying that we share which stays at human level .
Contrail designer
 
BoeingGuy
Posts: 6314
Joined: Fri Dec 10, 2010 6:01 pm

RE: Tristar Nose-up On Landing

Mon Mar 07, 2016 6:09 am

Quoting PGNCS (Reply 42):
Quoting BoeingGuy (Reply 41):
What if you are hand flying a visual approach? Then was it standard elevator inputs?

No. DLC is a function of being in the landing flap setting, not what kind of approach you are flying or what level of automation you are using. It is pure genius.

If you are flying a manual visual approach with no glideslope, then what causes DLC to change the spoiler inputs? Control wheel inputs?
 
Pihero
Posts: 4318
Joined: Mon Jan 31, 2005 5:11 am

RE: Tristar Nose-up On Landing

Mon Mar 07, 2016 9:52 am

Quoting BoeingGuy (Reply 44):
If you are flying a manual visual approach with no glideslope, then what causes DLC to change the spoiler inputs? Control wheel inputs?

Yes. As said earlier, once one has selected the landing flap configuration ( 33 or 42, as PGNCS said ), the DLC is *selected* and any input on the control column will move the DLC spoilers between 0° and 14°.

If the pilot needs more sink rate, for instance, thespoilers extend to 14°, and then for a further vertiucal speed demand, the tailplane would be moved... very effective but it will change the attitude.
Contrail designer
 
BravoOne
Posts: 3686
Joined: Fri Apr 12, 2013 2:27 pm

RE: Tristar Nose-up On Landing

Mon Mar 07, 2016 11:36 am

Some here have forgotten more than I ever new when I was actually flying the L1011. I do recall that with less than 100 hours time in the airplane I felt that was ready for a spot landing contest  The airplane was simply spot on when you aimed it for the TD zone. Having come from the DC10 there was no comparison in landing qualities.
 
PGNCS
Posts: 2257
Joined: Sun Apr 15, 2007 5:07 am

RE: Tristar Nose-up On Landing

Mon Mar 07, 2016 5:30 pm

Quoting Pihero (Reply 43):
Hi, PGNCS ! Long time no read !Quoting PGNCS (Reply 42): It is pure genius. For the crews flying her, in fact they all agreed that she was "PURE F...ING MAGIC"

Hi Pi! Feels good to be missed!   Just been flying too much to be online a lot. I (obviously) agree with your analysis of the L-1011 PFM!  
Quoting BoeingGuy (Reply 44):
If you are flying a manual visual approach with no glideslope, then what causes DLC to change the spoiler inputs? Control wheel inputs?

Normal yoke movement; there is no difference in what the pilots do.

Quoting BravoOne (Reply 46):
I do recall that with less than 100 hours time in the airplane I felt that was ready for a spot landing contest
Quoting BravoOne (Reply 46):
The airplane was simply spot on when you aimed it for the TD zone.

Absolutely! I have heard that the 1011 still has the lowest autoland dispersal of any aircraft. I can believe it; it always did a magnificent job, and sure made it easy to look good from up front!   It's the only plane I've flown that I actively miss.
 
User avatar
Florianopolis
Posts: 324
Joined: Sun Mar 29, 2015 2:54 pm

RE: Tristar Nose-up On Landing

Mon Mar 07, 2016 9:01 pm

Quoting Pihero (Reply 45):
If the pilot needs more sink rate, for instance, thespoilers extend to 14°, and then for a further vertiucal speed demand, the tailplane would be moved... very effective but it will change the attitude.

Was there a pitch moment as the center of lift moved around with the spoilers changing deflection? Was it too small to matter, or did some part of the PFM adjust trim automatically?
 
LU9092
Posts: 145
Joined: Thu Oct 18, 2007 2:09 am

RE: Tristar Nose-up On Landing

Tue Mar 08, 2016 2:11 pm

Quoting badgervor (Reply 31):

http://www.youtube.com/watch?v=yJLPW...GkZG0

I see little, if any flare before touchdown. Was it therefore easier to consistently "grease" a landing? It seems like changing the attitude to arrest the sink rate would be inherently more difficult, no? Reading all these lucky Tristar drivers wax nostalgic makes me wonder why Airbus or Boeing don't develop a similar approach. Does Lockheed hold a patent that prevents other manufacturers from implementing such a system?

Who is online

Users browsing this forum: atcdan, prebennorholm and 11 guests

Popular Searches On Airliners.net

Top Photos of Last:   24 Hours  •  48 Hours  •  7 Days  •  30 Days  •  180 Days  •  365 Days  •  All Time

Military Aircraft Every type from fighters to helicopters from air forces around the globe

Classic Airliners Props and jets from the good old days

Flight Decks Views from inside the cockpit

Aircraft Cabins Passenger cabin shots showing seat arrangements as well as cargo aircraft interior

Cargo Aircraft Pictures of great freighter aircraft

Government Aircraft Aircraft flying government officials

Helicopters Our large helicopter section. Both military and civil versions

Blimps / Airships Everything from the Goodyear blimp to the Zeppelin

Night Photos Beautiful shots taken while the sun is below the horizon

Accidents Accident, incident and crash related photos

Air to Air Photos taken by airborne photographers of airborne aircraft

Special Paint Schemes Aircraft painted in beautiful and original liveries

Airport Overviews Airport overviews from the air or ground

Tails and Winglets Tail and Winglet closeups with beautiful airline logos