United DC-8s Pt2: From Series 11s to 52s

Despite the relatively smooth testing phase and entry into service for the DC-8 the type didn't immediately meet its original range and performance guarantees, a fact that severely damaged its sales versus the Boeing 707. Donald Douglas Snr had however built his company on a reputation of personal integrity and was determined to meet the guarantees he had given. This pledge can be seen in the continuous updates that the initial DC-8-11 design received.

United Air Lines Douglas DC-8-51 N8007U Aeroclassics 1:400 Scale Model Airliner

As discussed in part 1 United was the joint launch customer (with Delta) for the DC-8 and had ordered 30 of the type. In fact the initial deliveries to United would stretch to 40 frames registered N8001U to N8040U - though they weren't all delivered in sequence. The first 18 frames were built as DC-8-11s with the JT3C-6 engine, which required water injection at take-off.  As far as I can tell only 16 aircraft were delivered to United in this configuration (N8004U-N8017U and N8019U-N8020U). N8018U was the first aircraft delivered as a DC-8-12.

I love this 1962 photo of DC-8s at San Francisco

The DC-8-12 was fitted with leading edge wing slots and extended wing tips. The type first flew on February 17, 1960 and was certified by July. The MTOW was also increased from 265,000 pounds to 273,000 pounds. United would modify all its DC-8-11s to DC-8-12 standard except for one - N8013U. This aircraft would have no doubt been modified but it was tragically destroyed on December 16, 1960 in a mid-air collision with a TWA Constellation. It was operating Flight 826 from Chicago to New York Idlewild at the time when approaching its destination its no 4 engine sliced open the Connie's fuselage top. The Connie broke into 3 sections and crashed immediately killing all 44 aboard. The DC-8 continued for a further 13.5 kilometres before crashing in Brooklyn. All 84 aboard the jet were killed plus a further 6 unfortunates on the ground.

Above: 1965 timetable from http://www.timetableimages.com/ttimages/ua.htm

Left: 1961 Air atlas route map

United would subsequently further upgrade all its DC-8-12s, again bar one,  during the 1960s. Mostly these became series 21s, with JT4A-9 engines (that didn't require water injection). This variant had an increased MTOW of 276,000 pounds. Interestingly United also upgraded just 5 of the DC-8-12s (N8007U-N8011U) to series 51s with the JT3D-1 Turbofan engine. I'm not sure why only such a small number were upgraded but these series 51s would outlive all the series 21s, albeit only for a year or two.

The DC-8-12 that never made it to being a series 21 was the last aircraft, N8040U. This aircraft was destroyed on July 11, 1961 operating a flight from Omaha to Denver Stapleton. Following departure the aircraft suffered hydraulics problems but continued to Denver. Further problems on landing caused the aircraft to leave the runway and crash into new taxiway construction equipment. The aircraft was destroyed in the resulting fire and 17 of the 115 passengers were killed, plus someone on the ground.

Of United's initial 40 frames three would actually be delivered as series 52s also (N8034U, 35U and 36U). The series 52 used the JT3D-3B engine, had a 4ft leading edge extension and strengthened landing gear. Its MTOW was increased to 300,000 pounds. The series 52 was certified on May 1, 1961.

United's first 40 DC-8s in delivery order with blue squares indicating variant upgrades

The remaining 38 aircraft would serve United well into the 1970s. Interestingly two of the three initial series 52s would be sold first (N8036U in 1970 and N8034U in 1971 - both to Air New Zealand) however the rest of the aircraft survived with United until a clearout began from late 1977. As is often the case with United aircraft most saw no further service after long careers with their first owner and many were traded to Boeing in part exchange for new 727s. Even so these 40 aircraft represented only just over half of the short United DC-8 fleet and 36 others arrived from March 1964. We'll take a look at these aircraft in part 3.

Note on Liveries

United had a selection of similar and thus confusing Mainliner livery variants from 1958 until the advent of the Saul Bass 'tulip' scheme in 1974. You'll notice that both the DC-8s above wear different schemes and neither are the same as the DC-8 delivery scheme featured in part 1.

Both have the updated slanted UNITED titles however N8007U has the updated shield ahead of the titles and red line separating the white from natural metal. N8008U has the crest moved to a small roundel on the nose and a gold line separating the white from natural metal.

This is odd as the crest with titles is usually with the gold and the roundel is usually with the red. United's schemes seem to have limitless variations of the basic setup however so I wouldn't necessarily suggest this is an Aeroclassics mistake.

The DC-8 delivery scheme, sported below by N8002U, differs from above by the larger titles in the shield and the line between that and the titles, small shield on nose, shorter main titles, gold line plus UNITED in big letters on the left wing.

References

Waddington, T. Great Airlines Series: Volume 2 - Douglas DC-8
Cearley, G.E. United: The Main Line Airway
Aviation Safety Network - N8013U
Aviation Safety Network - N8040U
Aeromoe's United Fleet