Older style airspeed indicators 757/767

JordanD

Honorary Member
This is going to seem like a really stupid question, but my experience is limited to jets that are 100% pure glass so I'm kind of curious. On the 757/767s with the older needle style airspeed indicators, what is there for low speed indications/low speed awareness? I'm used to the Embraer/320 where it can be kind of a moving target depending on flap setting/speedbrakes/or even turbulence where the low speed cue will shoot up and down depending on those things, but what kind of indication would you have without that? Speed cards and manually looking at the minimum maneuver speeds? What about the aforementioned instances here instantaneous load factors in turbulence or with the boards out are likely to cause variations in that?
 
I just wait until the stick shaker goes off, put down the newspaper, then casually increase thrust until situation resolved ;)

It was a weird adjustment coming from birds with all glass, but we use our white speed bugs to mark clean speed based on weight. Vref 30 + 80 for current gross weight, so if Vref at 30 degrees flaps is 120 knots, we'll be at 200 knots for a clean speed. By no means as accurate as glass tapes, but haven't practiced a stall yet. As much as I'll miss the fleet, it will be nice having glass again soon.
 
These dudes...

iu


Oh and as far as instantaneous changes, ignorance is bliss :)
 
This is going to seem like a really stupid question, but my experience is limited to jets that are 100% pure glass so I'm kind of curious. On the 757/767s with the older needle style airspeed indicators, what is there for low speed indications/low speed awareness? I'm used to the Embraer/320 where it can be kind of a moving target depending on flap setting/speedbrakes/or even turbulence where the low speed cue will shoot up and down depending on those things, but what kind of indication would you have without that? Speed cards and manually looking at the minimum maneuver speeds? What about the aforementioned instances here instantaneous load factors in turbulence or with the boards out are likely to cause variations in that?
Told Cards and Speed Bugs
One of the reasons being "told so" bugs people fast.
 
Bugs, PLI (a pitch limit indicator) and good old fashioned awareness.

Heading to Turkey out of JFK at a heavy weight, sometimes you’d get a little grumble of the stick shaker when you’re loaded up in the turn and retracting flaps if you weren’t careful.
 
I just wait until the stick shaker goes off, put down the newspaper, then casually increase thrust until situation resolved ;)

It was a weird adjustment coming from birds with all glass, but we use our white speed bugs to mark clean speed based on weight. Vref 30 + 80 for current gross weight, so if Vref at 30 degrees flaps is 120 knots, we'll be at 200 knots for a clean speed. By no means as accurate as glass tapes, but haven't practiced a stall yet. As much as I'll miss the fleet, it will be nice having glass again soon.
It's just as accurate. It's just not as simple or colorful. You actually have to do some work and understand some underlying information. Beware the difference between accuracy, and the shiny appearance of accuracy.
 
Bugs, PLI (a pitch limit indicator) and good old fashioned awareness.

Heading to Turkey out of JFK at a heavy weight, sometimes you’d get a little grumble of the stick shaker when you’re loaded up in the turn and retracting flaps if you weren’t careful.
That's sorta terrifying.
 
The PLI goes away when the flaps are up so all you have otherwise is the yoke shaking device. At least on the 75. I just went from round dials to glass with the upgraded 75/76 cockpits. It is kinda cool seeing the upper and lower margins on the speed tape. It funny to think all these years I didn't know how close to stick shaker I really was....
 
It's just as accurate. It's just not as simple or colorful. You actually have to do some work and understand some underlying information. Beware the difference between accuracy, and the shiny appearance of accuracy.
Work & understanding? Never heard of it.
 
On a heavy 76, the difference between flap retraction speed and Vfe can be surprisingly narrow for Flaps 1. You definitely have to pay attention.

Same with the 747, but mostly on approach. There’s such thing as being so heavy that you need to use flaps 25 because the gap between the high speed and low speed cue is too small, especially if it’s gusty
 
We have a watered down speed tape along with the round dials on our 76’s. I tend to look at the speed tape because that’s the habit I’ve formed from 12 years on an RJ. However, when decelerating, I look at the round dial for my flap speed bugs. I try to remember to use the round dial more in my scan, but hard to do when I only fly once or twice a month.


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What's up with that oil pressure gauge where the full-scale range is, like, 5X of the green band? When does it ever get that high?
After sitting here for a minute and thinking about it the only thing I can come up with is that when you start it up, or any TFE-731 for that matter, when it is really cold outside the oil pressure spikes because the bypass valve is closed longer.

Note that I could be totally wrong about this, it has been a long time since I flown one of these or thought about it. But I have flown a lot of 731s on other airframes and they all do it, at least I’m pretty sure they did it. Just has to be really cold out.

More likely it is just another #justlearjetthings, you get used to it. Like the all the differences with the electrical systems, 2 pressurization systems, different and backwards markings on the O2 bottles, different autopilots, and on, and on, and on.

Still a blast to fly and great first jet.
 
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