Remembering the DC-10: End of an era or good riddance?
The Lockheed L1011 was a luckier aircraft than the DC-10. The L1011 had two fan disk failures earlier on. I met the Eastern Air one at KJFK. The whole front of Nbr 3 had departed. There was a fan blade sticking into a passenger window penetrating the outer pane but not the inner. I believe it was TWA that had the other. All due to bad fan disk forgings, problems with the titanium. FAA didn't ground them but put a very short cycle limit on them and we became very proficient at changing fan disks. The two incidents never made much publicity as there were no pax injuries. Had the mass of the disk gone into the fuselage the press would have been all over it. Shee luck.
Later, in early 80's AN EAL L1011 tossed a nbr 2 fan disk. I stepped through the hole on the port side, the starboard hole was too jagged. Having four hydraulic systems saved the plane. Three were severed and U/S but the fourth, although dented, didn't let go. Had it done so there would have been no attempted landing. The flying stabilizer would have gone ANU or AND, an inside or an outside loop and that would have been it. Sheer luck or Grace of God if you please.
The RB211-22B suffered from Nbr 1 bearing fires resulting, if not immediately shutting down, in an uncontained fan disk release. They added fan grabbers and ultimately a detector to monitor bearing movement.
The L1011 had the best pax doors of any aircraft I worked on. The spring cartridge could be a hazard but it generally worked. Auto flight system stretched the state of the art. When working, the best and the pilots thought it one of the best flying aircraft of all time. Cockpit size, windows and general layout were good although the switchlights were a problem to maintain. Too frail for heavy fingers.
The elegant air inlet for nbr. 2 engine was sized for the Rolls engines. It was the smallest of the three big fans. It was impossible to fit GE or Pratts. This was a real problem when the Hyfil fan blades on the Rolls engines failed. Later we joked we were working an aircraft built by two bankrupt manufacturers.
Ultimately, the lack of growth potential in the design doomed it. Few were converted to freighters. Long range was achieved by shortening it. Even the -250 models did not match the DC-10 with its centerline gear.
So a lucky plane in that it avoided, initially, spectacular crashes but basically a domestic design with little freight potential.
Later, in early 80's AN EAL L1011 tossed a nbr 2 fan disk. I stepped through the hole on the port side, the starboard hole was too jagged. Having four hydraulic systems saved the plane. Three were severed and U/S but the fourth, although dented, didn't let go. Had it done so there would have been no attempted landing. The flying stabilizer would have gone ANU or AND, an inside or an outside loop and that would have been it. Sheer luck or Grace of God if you please.
The RB211-22B suffered from Nbr 1 bearing fires resulting, if not immediately shutting down, in an uncontained fan disk release. They added fan grabbers and ultimately a detector to monitor bearing movement.
The L1011 had the best pax doors of any aircraft I worked on. The spring cartridge could be a hazard but it generally worked. Auto flight system stretched the state of the art. When working, the best and the pilots thought it one of the best flying aircraft of all time. Cockpit size, windows and general layout were good although the switchlights were a problem to maintain. Too frail for heavy fingers.
The elegant air inlet for nbr. 2 engine was sized for the Rolls engines. It was the smallest of the three big fans. It was impossible to fit GE or Pratts. This was a real problem when the Hyfil fan blades on the Rolls engines failed. Later we joked we were working an aircraft built by two bankrupt manufacturers.
Ultimately, the lack of growth potential in the design doomed it. Few were converted to freighters. Long range was achieved by shortening it. Even the -250 models did not match the DC-10 with its centerline gear.
So a lucky plane in that it avoided, initially, spectacular crashes but basically a domestic design with little freight potential.
The L1011 had two fan disk failures earlier on.
NYC73AN125
DCA81AA027
Scary stuff.
I didn't imply it was "luck: that Lockheed had four hydraulic systems in the L1011. They had to provide redundancy for the flying stabilizer which gave the plane its superb handling. It was however "luck" that the fourth system was only dented and not pierced. That nbr. 2 engine fan disk had released and chewed its way forward right through the "S" duct and came apart just short of the rear pressure bulkhead. Had it continued just a short distance more it would have taken out the rear pressure bukhead and there would have been an explosive decompression. So that was "luck" too. There were a series of dings in the top of the stabilizer box where it marched forward.
It was also "luck" that sent the two defective disks away from the airplane instead of into the fuselage.
I agree that the DC-10 design of cable drives on the slat drives was not as good as the jackscrew systems on the L-1011. It too had its faults though and I saw several zero flap, zero slat landings at KJFK due to faults in the slat assymetry system. No real problem but a very fast landing at a flatter body angle than normal.
The L1011 was more advance than the DC-10. Its DLC system on landing let it maintain a constant body angle on approach so it looked like it was running on a set of rails. No pitching an porpoising in rough air the way other aircraft did to maintain their glide path.
It was also "luck" that sent the two defective disks away from the airplane instead of into the fuselage.
I agree that the DC-10 design of cable drives on the slat drives was not as good as the jackscrew systems on the L-1011. It too had its faults though and I saw several zero flap, zero slat landings at KJFK due to faults in the slat assymetry system. No real problem but a very fast landing at a flatter body angle than normal.
The L1011 was more advance than the DC-10. Its DLC system on landing let it maintain a constant body angle on approach so it looked like it was running on a set of rails. No pitching an porpoising in rough air the way other aircraft did to maintain their glide path.
Join Date: Mar 2014
Location: Toronto
Posts: 1
Likes: 0
Received 0 Likes
on
0 Posts
Is this the last passenger flight of a DC-10?
