Hey there AIRLINERS.NET community! My name is Adam, I have a question about yelling clear prop before starting an engine. The question is how long should you yell it before you start the engine... I see pilots yell it, but before anyone would ever have the chance to move away from the aircraft the engine is already started. which kind of defeats the purpose. Please leave a reply on this topic.

Thanks, Adam.

Thanks for the reply @GalaxyFlyer

One of the funniest things I've seen flying the 727 was when we had a Captain that would open up the sliding window and yell that before we started the engines.

tb727 wrote:

One of the funniest things I've seen flying the 727 was when we had a Captain that would open up the sliding window and yell that before we started the engines.

Challenge accepted for when I make captain.

Starlionblue wrote:

tb727 wrote:

One of the funniest things I've seen flying the 727 was when we had a Captain that would open up the sliding window and yell that before we started the engines.

Challenge accepted for when I make captain.

Take video please.

Starlionblue wrote:

tb727 wrote:

One of the funniest things I've seen flying the 727 was when we had a Captain that would open up the sliding window and yell that before we started the engines.

Challenge accepted for when I make captain.

I am so going to start doing that

Canada1Pilot wrote:

Hey there AIRLINERS.NET community! My name is Adam, I have a question about yelling clear prop before starting an engine. The question is how long should you yell it before you start the engine... I see pilots yell it, but before anyone would ever have the chance to move away from the aircraft the engine is already started. which kind of defeats the purpose. Please leave a reply on this topic.

Thanks, Adam.

I have never seen anybody do it, nor have I ever done it myself. IMHO, it makes sense for a large taildragger where you can't see what's in front of you, but it doesn't make that much sense in a Piper or Cessna.

I always open the window, yell it, then start the beacon, check left, check right, and then start up. That typically gives 5-10 seconds for someone to holler if they're down there.

A week is too long

trpmb6 wrote:

Starlionblue wrote:

tb727 wrote:

One of the funniest things I've seen flying the 727 was when we had a Captain that would open up the sliding window and yell that before we started the engines.

Challenge accepted for when I make captain.

Take video please.

I'm not there anymore otherwise I would. I almost peed my pants the first time I flew with him and he did that, I was laughing that hard. He did it straight faced too. I mean he yelled it so loud you could probably hear him over the APU. I can still picture it and hear it in my head clear as day and this was probably 7-8 years ago!

The problem on the 350 is that you can't open the windows. Clearly a flaw in the design. I guess it might add to the comedy if I popped my head out of the overhead hatch.

Starlionblue wrote:

The problem on the 350 is that you can't open the windows. Clearly a flaw in the design. I guess it might add to the comedy if I popped my head out of the overhead hatch.

It seems like opening cockpit windows
are becoming a thing of the past on
newer designs


I don’t think the 787 has them either


Always liked sliding the window open after landing on a nice day

A friend of mine sent me a Snapchat video of him yelling "clear prop" and turning on the engine. It was a novelty airplane propeller for his car a/c!

Max Q wrote:

Starlionblue wrote:

The problem on the 350 is that you can't open the windows. Clearly a flaw in the design. I guess it might add to the comedy if I popped my head out of the overhead hatch.

It seems like opening cockpit windows
are becoming a thing of the past on
newer designs


I don’t think the 787 has them either


Always liked sliding the window open after landing on a nice day

I didn't know that the new wide-bodies don't have them! That's too bad. I love having a window that opens, so nice on nice days to get some fresh air. Opened them in flight on the Falcon a couple times.

Starlionblue wrote:

The problem on the 350 is that you can't open the windows.

So fly something else. Problem solved.

tb727 wrote:

Max Q wrote:

Starlionblue wrote:

The problem on the 350 is that you can't open the windows. Clearly a flaw in the design. I guess it might add to the comedy if I popped my head out of the overhead hatch.

It seems like opening cockpit windows
are becoming a thing of the past on
newer designs


I don’t think the 787 has them either


Always liked sliding the window open after landing on a nice day

I didn't know that the new wide-bodies don't have them! That's too bad. I love having a window that opens, so nice on nice days to get some fresh air. Opened them in flight on the Falcon a couple times.

Agree, nice to get some fresh air in



What was that like, opening the
windows in flight ?

Just a little noisy, not much wind inside. Similar to going down the freeway with your window down except I wouldn't stick my arm out!

tb727 wrote:

Just a little noisy, not much wind inside. Similar to going down the freeway with your window down except I wouldn't stick my arm out!

Interesting, I think it’s designed that way
How fast were you going ?

Less than 200, IIRC that was the window speed.

tb727 wrote:

Less than 200, IIRC that was the window speed.

I’d like to try it, about as close you
can get to an open cockpit in an
airliner !

Huh, I never realized the 787 and 350 have cockpit windows you can't open.

I think not having openable windows on the A350 and 787 was a question of weight and complexity. The side windows on the 350 and 787 are huge. They're also irregularly shaped, and more importantly not flat, so they might be hard to mount on rails.

A350. The frontmost side window is large and non-flat. Incidentally, you can see the escape hatch top right above the engineering screen. You get up there by stepping on the observer seat, then the desk, then the little shelf with the yellow/black tape and finally the top of the closet.



787 side window is even more gigantic, as they've opted for only one instead of two. No way that will be openable.



By contrast, the A330 side window is flat (as far as I can tell), smaller and has more or less parallel top and bottom edges, so can run in rails backwards. You still get adequate field of view since the window is much closer to the pilot. You can see the large black handle for the window in front of the tablet, above the sidestick.

Good point about the larger
windows although the 75/6
and 777 have big windows
and they can be opened


The L1011 and B747 had a hatch instead
of opening windows


They could be opened on the DC10
and MD11


On later Boeing’s these larger
windows are heavy and require
cranking to open and close, unlike
the 707/ 727/ 737 where you just
pull a latch and they slide back


I think all future aircraft will go
to an overhead hatch, kind of
a shame

I think the move away from the sliding windows (at least on Boeing products) may be due to the issues we had on 777/767 window #2 that would sometimes slide open on take off roll. I believe they have a fix in place now, but it's not as easy to open now either because of this.

VSMUT wrote:

[I have never seen anybody do it, nor have I ever done it myself. IMHO, it makes sense for a large taildragger where you can't see what's in front of you, but it doesn't make that much sense in a Piper or Cessna.

I think it's a good practice regardless. Plenty of Cessna and Piper models were built with tailwheels btw

trpmb6 wrote:

I think the move away from the sliding windows (at least on Boeing products) may be due to the issues we had on 777/767 window #2 that would sometimes slide open on take off roll. I believe they have a fix in place now, but it's not as easy to open now either because of this.

Windows closed and locked was the first
item on our before start checklist on
the 75/6

Max Q wrote:

Interesting, I think it’s designed that way

tb727 wrote:

Just a little noisy, not much wind inside. Similar to going down the freeway with your window down except I wouldn't stick my arm out!

The openable windows on the DC-8 & MD11, and presumably the DC-10, are called clearview windows. A quick look at the AOM indicates that they may be opened in flight (unpressurized) as part of the SMOKE/FUMES REMOVAL checklist.

Max Q wrote:

trpmb6 wrote:

I think the move away from the sliding windows (at least on Boeing products) may be due to the issues we had on 777/767 window #2 that would sometimes slide open on take off roll. I believe they have a fix in place now, but it's not as easy to open now either because of this.

Windows closed and locked was the first
item on our before start checklist on
the 75/6

Yes but I am aware of incidences of the #2 sliding open nonetheless. Had to do with the mechanism that is now changed which should resolve the issue.

I recall a biz jet I flew years ago, IA 1125, had an opening Pilot window called a “direct vision window” presumably because there was nothing to obscure the pilot’s vision when opened? Never opened it in flight of course. It might have been a certification requirement. I don’t see any modern large biz jet with cockpit windows that can be opened now.

26point2 wrote:

I recall a biz jet I flew years ago, IA 1125, had an opening Pilot window called a “direct vision window” presumably because there was nothing to obscure the pilot’s vision when opened? Never opened it in flight of course. It might have been a certification requirement. I don’t see any modern large biz jet with cockpit windows that can be opened now.

Yep, DV windows are what the smaller
sliding windows were described as

fr8mech wrote:

The openable windows on the DC-8 & MD11, and presumably the DC-10, are called clearview windows. A quick look at the AOM indicates that they may be opened in flight (unpressurized) as part of the SMOKE/FUMES REMOVAL checklist.

I remember reading the emergency smoke evac procedure for the E-4B. Last resort was open door 1 and 4 in flight. You were cautioned to secure your self to the handle next to the door (a neck tie was identified as being suitable if nothing else was available). Can;t say of the procedure was limited to the E-4B, or was also in the 747-200 manual.

FrmrKSEngr wrote:

fr8mech wrote:

I remember reading the emergency smoke evac procedure for the E-4B. Last resort was open door 1 and 4 in flight. You were cautioned to secure your self to the handle next to the door (a neck tie was identified as being suitable if nothing else was available). Can;t say of the procedure was limited to the E-4B, or was also in the 747-200 manual.

Now, I seem to recall a strap that was stowed near the L1 door on our Jumbos. It was about 8 inches long and could be installed between the door and door frame. Never knew what it was for, but was part of our emergency equipment inventory.

fr8mech wrote:

The openable windows on the DC-8 & MD11, and presumably the DC-10, are called clearview windows.

Same name on the DC-9/MD-80/MD-90/717.

I'm guessing the DC-8 windows leak water and deicing fluid too, since it's basically the same windscreen design as the DC-9. Was McD smart enough to fix this on the DC-10/MD-11?