If you look at the cockpit of a general aviation aircraft, let alone a jet airliner, it looks to be a complicated pile of gauges and knobs and levers of various kinds, perhaps not unlike the tangle of gauges, valve handles, and levers on a steam locomotive backhead.
On the other hand, aircraft gauge layouts tend to follow standardized patterns, and the levers that control flight are quite logically arranged.
For however high tech an airplane is, the controls follow a very simple principle: moving a lever or a control forward means "gid'yap" and backward means "whoa" For example, a single-engine general aviation airplane with a piston engine and constant speed prop has levers for prop speed, throttle, and mixture. If you want to "gid'yap", say for takeoff or if you need to speed up in a hurray, you push all three levers forward. Likewise, to slow down, you certainly pull the throttle back, and you may also pull back on prop and mixture depending on flight conditions.
In the airplane, however, how fast you go vs how fast you climb is some tradeoff between operating the engine controls (prop, throttle, and mixture) and the control column. On the other hand, if you need to gain speed in a hurray, say, to recover from a stall or a downdraft, you "firewall" (push full forward) all three engine controls and you push the control column or wheel or stick forward.
For the steam locomotive, on the other hand, I was under the impression that the throttle is commonly overhead, and that the engineer pulled back to open the throttle but pushed forward to close the throttle. Like the general aviation aircraft, the engine controls on the steam locomotive are not single-lever: for the steam locomotive, there is also the reverse or "Johnson bar." Some earlier locomotives, I believe, actually had a lever with a locking quadrant, and actual Johnson bar, but I understand that later locomotives had some kind of steering wheel control to allow more precise control of the reverser setting, crucial to economizing on steam. So the throttle and reverse control are in a way analogous to the throttle and prop speed on the airplane, where you want to operate wide open throttle but with reduced prop speed at cruise to get good fuel economy in the airplane.
As to which way the brake handle operates I have no idea or whether it follow the gid'yap-whoa convention or not.
So can other comment on what is known about the layout of controls on steam, Diesel, and electric locomotives, and whether there is a logic to them or just happenstance of early designs? Perhaps the gid'yap-whoa convention is more important on an airplane to have everything consistent, but it is better to keep the perhaps inconsistent controls on locomotives because locomotive engineers are trained on them and to change would cause more accidents than it would prevent?
If GM "killed the electric car", what am I doing standing next to an EV-1, a half a block from the WSOR tracks?
I know as a conductor that the controls for both EMD and GE power are essenically the same . Whether its a desktop or convenstional stands they are both laid out the same, Now I cant speck for the earlier diesels such as ALCO LIMA HAMLITON OR BALDWIN I have never seen the control stands in these types of units. But now in both the EMD and GE units the throttle, brake stands and horn and alerter contriols are laid out the same Hope this he;ps Larry
The major controls on a steam locomotive are relatively consistent. The throttle, brakes, and reversing device are pretty much in the same place on almost all locomotives.
Steam locomotive throttles were usually above the head of the engineer simply because they needed to travel so far. There is quite a bit of leverage, measuring from the pivot point to the point the throttle rod is connected compared to the handle end the engineer pulls. Remember, the old time throttles had no power assist.
The Johnson Bar or the wheel reverse were simply two different designs for reversing the direction or controlling the cutoff. The jet engines do reverse, but the thrust reversing (or pitch reversing on a prop) is used for braking (closer to a diesel's dynamic braking), rarely for backing up an airplane. The reverse section is a small percentage of the throttle on an aircraft.
Since a locomotive is always on the ground (we hope), and not affected by downdrafts or a need to climb, there's no need for sudden increase in power, which would probably slip the wheels anyway.
The brakestand in a diesel is almost identical to the one in a steam locomotive, and probably made by the same company.
cprtedI have zero knowledge of aircraft, so I simply don't know if your plane analogy works. As for the throttle/cut off relationship, the throttle regulates how much steam is admitted from the boiler into the steam chest. The cut off regulates how much steam is admitted from the steam chest into the cylinders.
My question wasn't so much about the separate functions of the throttle and the Johnson bar/reverser/valve timing control, although there is some analogy between the reverser setting and the prop pitch on a propeller airplane. And I have seen (and been on jets!) where reverse thrust is used to back jets out of gates at Minneapolis/St Paul, and it is a little bit of a wild, lurchy ride from a passenger perspective.
My question was about ergonomics of the control. The steam locomotive throttle is pulled back to make the locomotive go, forward when the reverser is set up for the normal direction of travel. It seems like a more logical way is to push the throttle forward to make it "go" and pull it back to make it stop.
Does the locomotive engineer pull back on a Diesel locomotive throttle to increase power? I had recently seen an article on the Budd RDC, and it seemed the control lever was moved up (and somewhat forward) to apply power. Chicago El trains, at least back in the day, had a "trolley car" style controller where the dial is turned clockwise to make it go, turned counterclockwise to engage blended dynamic and friction braking -- the United Aircraft TurboTrain also had this trolley car type controller.
-Don (Random stuff, mostly about trains - what else? http://blerfblog.blogspot.com/)
Paul MilenkovicMy question was about ergonomics of the control. The steam locomotive throttle is pulled back to make the locomotive go, forward when the reverser is set up for the normal direction of travel. It seems like a more logical way is to push the throttle forward to make it "go" and pull it back to make it stop.
TomDiehl The Johnson Bar or the wheel reverse were simply two different designs for reversing the direction or controlling the cutoff. The jet engines do reverse, but the thrust reversing (or pitch reversing on a prop) is used for braking (closer to a diesel's dynamic braking), rarely for backing up an airplane. The reverse section is a small percentage of the throttle on an aircraft.
Never too old to have a happy childhood!
BaltACDWhat it cost in fuel, I have no idea.
About 200 #s of fuel powering back --- 27 Gallons. Waiting time to disconnect on a regular push back about 5 minutes to get fully disconnected. (stopping, Brakes set, disconnecting, pulling tow bar away, getting clear signal to taxi so the idle fuel flow about 16.6 # per minute per JT-8D engine. So 50#/ minute -- 727 33# / minute DC-9. Only EAL Air Craft normally powered back.
TomDiehlSince a locomotive is always on the ground (we hope),
Surely you mean "always on the rails, and never on the ground."
Johnny
oltmanndYes. Push the levers forward to stop, pull them back to go. Reverser goes in the direction of travel.
That's pretty much the sum total of the logic.
Larry Resident Microferroequinologist (at least at my house) Everyone goes home; Safety begins with you My Opinion. Standard Disclaimers Apply. No Expiration Date Come ride the rails with me! There's one thing about humility - the moment you think you've got it, you've lost it...
Deggesty TomDiehlSince a locomotive is always on the ground (we hope), Surely you mean "always on the rails, and never on the ground." Johnny
Well, since the rest of the quote was comparing it to an aircraft.......
BaltACD TomDiehl The Johnson Bar or the wheel reverse were simply two different designs for reversing the direction or controlling the cutoff. The jet engines do reverse, but the thrust reversing (or pitch reversing on a prop) is used for braking (closer to a diesel's dynamic braking), rarely for backing up an airplane. The reverse section is a small percentage of the throttle on an aircraft. You never flew Eastern Airlines, when they were in business. They always backed their planes away from the loading area using engine power and the thrust reversers. I guess they felt it saved them the cost of the push bar, push car and the personnel to operate it. What it cost in fuel, I have no idea.
No, 20 years in the Air Force and I only saw them back up a C-141 like that once.
I fly every week, usually US Air or American. I average 4 to 5 engine reverses a year from the gate.
Locomotive throttles aren't the only examples of 'reverse ergonomics.' Tillers on boats go back a lot farther in time - push to port, turn to starboard and vice versa.
In most cases, the operator has to adapt to the controls, not vice-versa.
Consider automotive braking systems, which work both ways. Emergency/parking brake pulls toward, foot brake pushes away (the same as, and right next to, the throttle - seemingly a recipe for disaster!)
Controller positions on modern diesels are in the same relationship to the operator, and act in the same ways, as the control stands on the subway cars I rode on to go to high school. When it comes to changing the locations/functions of controls, the wise designer will probably try to retain the relationships that experienced operators are comfortable with. Maybe things would be different if Stephenson had set up the throttle on the Rocket to open with a forward push...
Chuck (Former aircraft maintainer)
At least you are less likely to accidentally bump it and go faster.
tomikawaTT Locomotive throttles aren't the only examples of 'reverse ergonomics.' Tillers on boats go back a lot farther in time - push to port, turn to starboard and vice versa. In most cases, the operator has to adapt to the controls, not vice-versa. Consider automotive braking systems, which work both ways. Emergency/parking brake pulls toward, foot brake pushes away (the same as, and right next to, the throttle - seemingly a recipe for disaster!) Controller positions on modern diesels are in the same relationship to the operator, and act in the same ways, as the control stands on the subway cars I rode on to go to high school. When it comes to changing the locations/functions of controls, the wise designer will probably try to retain the relationships that experienced operators are comfortable with. Maybe things would be different if Stephenson had set up the throttle on the Rocket to open with a forward push... Chuck (Former aircraft maintainer)
"I Often Dream of Trains"-From the Album of the Same Name by Robyn Hitchcock
Our community is FREE to join. To participate you must either login or register for an account.