Here is a snippet from a training video by the National Bus Company in the UK. Just based on the cars in the background, I’d place it being made around the late 1970’s. The first part of the video is a test – identify all the things the bus driver is doing incorrectly. The Narrator then offers feedback, some with typical understated British humor. I didn’t do very well – I only found three. But I did learn a few new tricks for driving a bus, and the technical explanations by the Narrator are interesting.
The bus in this video is a Leyland National, built from 1972 to 1985, and was styled by Giovanni Michelotti – who had previously styled a number of British Leyland products (TR4, Spitfire, GT 6, etc.). The National was introduced to replace the older Leyland Panther, Daimler Roadliner and AEC Swift single-decker coaches. It had many modern upgrades; air suspension, semi-automatic transmission, etc.
The engine was an 8.2 litre (500 cu in) Leyland 510 turbocharged inline six cylinder diesel. It was unique in how it was positioned – it was mounted in the back, transversely, in lay down fashion (horizontally) with the cylinders facing to the rear. It was also unique in that it had a fixed head – Leyland’s previous engine had problems with blown head gaskets, so this fixed that problem. Unfortunately, it created others – changing pistons meant you had to go from the bottom of the engine up. The 510 proved troublesome in other areas also and had a reputation for being loud. Most were replaced with Volvo or Gardner engines.
The National was offered in three lengths, the most popular being the 11 meter model which carried 44 passengers.
It was given a face-lift in 1979 with a new rounded front fascia and movement of the radiator to the front. Leyland also replaced the 510 engine with the 0.680 (here in a transverse vertical orientation).
Early in its production run, several were modified as rail car demonstrators – but railway operators expressed little interest.
When re-engined, the National was a popular coach with over 7,000 made.
So, how’d you do on the quiz?
Additional Information:
Interesting video and the mistakes were fairly obvious, just pity the narrator doesnt know how air brakes work, its the exact opposite to how a hydraulic system in you car operates air pressure releases the brakes dropping pressure by stepping on the brake pedal applies them, no air pressure means the brakes come on hard and you stop untill pressure builds again, coasting is just dangerous in a heavy vehicle at any time.
Bryce, as a professional truck driver please tell me that you were kidding and that you really do know how truck air brakes work! You’ve got it backwards.
Truck service air brakes use an increase in air pressure to activate the brakes. Yes, the parking/emergency brake is spring loaded, and requires air pressure to release it, but not the service brake.
Having once driven a truck that had low air pressure and whose low air pressure alarm wasn’t working, I can tell you most assuredly it was not a pleasant experience!
If I’m not mistaken, it’s railroad air brakes that operate that way. If a hose coupling opens up, say from a string of cars getting uncoupled, the cars’ brakes get no air pressure so they engage, keeping them from becoming runaways.
I found a couple of blunders, though some of the mechanical nuances escaped me. In his first appearance, though, our narrator/interrogator seems to have broken his neck. I’m sure there’s a good operator-mistake story behind that one. “Rule 1: Don’t stress the gears. Rule 2: Don’t run over your passengers!”
Not quite correct there Kiwi, air brakes use air pressure to apply the service brakes. You step on the pedal and air is sent to the brake chambers to make a brake application, usually on all of the axles. The parking brake works as you stated using air pressure to hold the parking brake spring compressed when you want to move. These are usually on the non steering axles and only take about 60 psi of pressure to release. Everything built in the U.S. since 1977 has a dual circuit air system(front/rear) that gives you the ability to stop the vehicle with the service brake pedal even if you loose one of the two circuits.
It seems odd that they were still messing around with semi-automatics based on the old Daimler Fluid Flywheel in the ’70s.
Stylistically, the Leyland National is a missing link in bus styling with no direct American equivalent being cleaner and more modern than a New Look but not at all futuristic like the RTS.
On the way to looking up something else, I found out that, in addition to the railcar, Leyland and British Rail tried to make a regular non-powered coach out this bus. It seems to have been a bus body stretched out and up and mounted on the undercarriage of an obsolete Mk1 coach. It proved to be just as unpopular with passengers as GM’s earlier bus-to-train “Aerotrain” and only one demonstrator was built.
What I find interesting is the part where he is coasting down the hill, lots of time spent on the damage that will do to the transmission and brakes but no time spent on the fact that when those brakes overheat you may not be able to keep the bus on that curvy road or stop at the bottom.
I do have to wonder about the engineering decisions behind making a power steering system that does not get hydraulic pressure if the transmission isn’t in gear, particularly on a transmission that you need to pause in neutral before selecting the next gear, not to mention that the transmission doesn’t get lube when it isn’t in gear.
Scoutdude said:
“I do have to wonder about the engineering decisions behind making a power steering system that does not get hydraulic pressure if the transmission isn’t in gear, particularly on a transmission that you need to pause in neutral before selecting the next gear, not to mention that the transmission doesn’t get lube when it isn’t in gear.”
My thought as well- Using the drive line as a source of hydraulic power simplifies things and saves a bit of money, but if the drive line produces no hydraulic pressure in neutral (and it certainly could- the crankshaft is still spinning), it seems like a false economy.
+1
I failed. Picked only the idling-in-gear thing, really.
What a rubbishy gear system that REQUIRED a passenger-tipping delay in each shift. We had such system on these buses here and it was herky-jerky when, it seems, being driven as intended.
Air systems that run down if idling, gearbox bearings unlubricated if in neutral and rolling, 1940’s-tech fluid flyhweels and unsuccessful engines with fixed heads because previous efforts from them blew gaskets (not to mention a torque peak at what seems very high revs for a workaday slow-moving application), what on earth happened to the great British engineering enterprise, certainly once the greatest in the world?
Great post, especially as it got me in even though about a screamy, smelly and twitchy vehicle I detested as a public- transport kid.
Sadly, the Leyland National as a train iidea did make it to fruition, in the truly awful British Rail Pacer trains – four wheeled (two axle) freight wagon chassis with a bus body crudely bolted in the top. Hard to believe, but true, and the CC I was pondering is now pushed up the queue.
I also had the experience of having spring set parking brakes set unexpectedly. My truck had a divided air tank whose pressure gauge registered on only one half of the tank. On a frigid morning, with the pressure gauge reading normal, frozen condensation prevented the other half of the tank from maintaining pressure, and it was this half which held the “maxi-brake” released. Out of the blue, at a mercifully low speed, the brakes suddenly locked both rear sets of dual tires. In those days, the parking brake was not modulated, as it was later; it was all or nothing. My truck skidded across a snow covered road, narrowly missing a telephone pole and an oncoming car, and came to rest with no damage. When we were able to heat the air reservoir to melt the frozen condensation, we got several gallons out of the tank which evidently was not drained when I blew down the tanks. The company installed air dryers for the brake sysems after that! The things that happened back then that we survived………..