BusTalk

[Q65A]

In 1977, NYCT and MaBSTOA each took delivery of sizable fleets of Gen. 4 Flxible New Looks. These buses would be the last New Look transits purchased by either agency. In September of that same year, veteran Long Island-based aerospace contractor Grumman Corporation announced their intention to purchase Flxible from former parent Rohr Industries, a $55 million deal that was consummated officially in January 1978. The deal appeared to be a classic “win-win” situation. For Grumman, the acquisition was an attractive one: the diversified company already owned other automotive businesses (i.e. manufacture of fire apparatus and aluminum truck bodies) and transit ridership was on the rise in the late 1970’s. It was anticipated that many new buses would be needed to meet the increased demand. For financially struggling Rohr, the transaction likely was more bittersweet. Flxible had been a profitable subsidiary even as the rest of Rohr’s business portfolio declined in value, but the deal with Grumman provided a badly needed infusion of cash. For some time prior to the Grumman acquisition, Rohr already had been developing a new ADB, which was introduced to the U.S. transit industry as the Grumman-Flxible Model 870 on May 9, 1978 (nearly 5 months after Rohr’s ownership of Flxible had passed to Grumman). While arch-rival GM had suspended Fishbowl production at its Pontiac, MI plant in March 1977, Grumman-Flxible continued to produce both New Looks and 870’s simultaneously at its Loudonville and Delaware (Ohio) plants until October 31, 1978 (when the final 5 New Looks were delivered to Metro Regional Transit, Akron, Ohio). The Model 870 was offered in a series of industry-standard configurations: 35- and 40-foot lengths, 96” and 102” widths, and a choice of 3 Detroit Diesels(the 6V-71N, the 6V-92, or the 8V-71N) driving an electronically-controlled Allison V-730 hydraulic transmission. The Model 870 model numbering system was very similar to the system introduced with the Gen. 3 Flxible New Looks. The first 2 digits indicated nominal seating capacity, while the next 3 digits (096 or 102) indicated coach width; the Model 870 system added a single numeral (6 or to indicate whether a 6- or 8-cylinder Detroit was installed. However conventional the powertrain specifications and dimensional configurations may have been, the Model 870 was radically different from older Flxible products and other transit buses. The modern-looking Model 870 was handsome but quite square as compared to curvaceous Fishbowls or well-rounded Old Looks. Bus industry observers legitimately might contend that the 870 was the first in a long line of boxy-looking ADB’s, a design trend that persists to this day. The 40-foot coach rode a 299” wheelbase and was 118.9” tall. An asymmetric 2-piece windshield was used. As had been done previously on GM Old Looks, the windshield on the operator’s side slanted rearward from bottom to top to eliminate glare (a feature that would be repeated later on Orion V’s). The windshield was kept clean by a pair of air-operated pantograph-type wipers; each wiper was controlled by an individual knob located on the left side of the front instrument panel. A large front destination sign (flanked by a pair of amber hoodlum lights) crowned the top of the front, with provision for a side sign installed at the top of the first curbside passenger window. In classic fashion, a hinged run number box was installed atop the right hand side of the front windowsill. Passenger windows were tinted and sealed, and an automatic HVAC system handled all climate control requirements. The bus operator had a small sliding window with which to adjust the roadside rearview mirror. The rear window area was completely blanked off, and the area formerly encased in a rear windshield now was occupied by HVAC equipment. A 4-leaf jackknife front entrance door was used (another feature reminiscent of GM and Mack Old Looks) as was a kneeling front suspension. A hydraulically operated wheelchair lift optionally could be mounted in the entrance door stepwell. This arrangement would permit wheelchair passengers to board or alight while the operator remained seated. The rear door was a 2-leaf, flat push-type. Ergonomics finally had become a much more important consideration in bus operator workstation designs. The bus operator’s fully adjustable mechanical seat now was mounted to an elevated, expanded metal platform that was suspended a short distance above the main floor level. Unlike the contemporary GM RTS, the steering wheel angle was not adjustable. Directional signal switches were floor mounted, as had been common practice on most GM and Flx New Looks. The operator faced a fully-instrumented front gauge panel, now equipped with a squared central telltale panel. Gone forever was the left-hand A-pillar mounted vertical “bug light” panel used on Flxible New Looks. Toggle switches and a rotary master switch were mounted on a backlit left hand switch panel, as was the standard 5-position rotary door control handle. The automatic transmission selector (also mounted on the LH switch panel) consisted of a toggle switch with an adjacent vertical row of indicator lamps, the illumination of which indicated specific gear selection. The DD3 parking brake valve was mounted to a bracket at the right front corner of the operator’s seat. As the primary designer of the 870, Rohr clearly wanted to minimize parts inventories and to expedite manufacture and assembly of production buses. To achieve these objectives, Rohr engineers made extensive use of elaborate aluminum extrusions designed to be assembled with a greatly reduced number of fasteners, which would reduce both overall parts counts and total assembly time. The design team also sought to use as many pre-produced major subassemblies as possible, another move intended to maximize manufacturing speed and efficiency. Such pre-fabricated assemblies were produced in-house at Loudonville or at third-party manufacturing facilities, and were trucked to Delaware for quick final assembly. This type of subassembly construction differed from the modular construction concept used by the GM RTS. While Flxible made extensive use of aluminum in framing and side panel construction, GM used heavily braced stainless steel modules and fiberglass side panels, and did not appear to be particularly concerned about reducing total fastener or parts requirements. Rohr’s engineers appeared to have achieved their design objectives with the Model 870: the total number of fasteners was reduced to 4,000 (from about 16,000 fasteners used on conventional buses), and the overall number of parts required was 9,000 (down from about 31,000 parts used on other buses). One of the design features peculiar to the Model 870 was an A-shaped frame (“A-Frame”) that served as the location point for the rear axle and suspension. The apex of the 350-pound A-frame was attached with a single clevis bolt to the rear of the “fuel bolster” (i.e. the transverse plate located just aft of the fuel tank) while each “leg” of the A-frame was welded to a transverse crossmember installed immediately forward of the front portion of the engine cradle. As history later would demonstrate, this design feature would prove to be a serious liability under certain operating conditions.

[Catfish 44]

Excellent piece, well written as are your other essays

[Mr. Linsky]

Bob,

I echo Catfish 44's sentiments exactly - you've done it again!

You should start thinking in terms of a book because all of your tutorials are priceless!

BTW; give me some fleet numbers on the Generation 4's and I'll do the pictures.

Mr. Linsky - Green Bus Lines, Inc., Jamaica, NY

[Waynejay]