Aces High Bulletin Board

General Forums => The O' Club => Topic started by: MachFly on June 06, 2011, 02:18:23 AM

Title: "Superchargers low and latched"
Post by: MachFly on June 06, 2011, 02:18:23 AM
I was watching Pear Harbor the other day and I'm trying to understand one of the call outs. Just before the first B-25 started rolling (02:34:01) there was a call out "Superchargers low and latched". Does anyone know what the word "latched" means in this context?

Thanks
Title: Re: "Superchargers low and latched"
Post by: Pigslilspaz on June 06, 2011, 02:40:28 AM
If it's from Pearl Harbor, there is a chance they made that up, could be wrong though.
Title: Re: "Superchargers low and latched"
Post by: rpm on June 06, 2011, 03:42:22 AM
http://www.wingsacrossamerica.us/wasp/check_list.htm

Before take off (Pilot answers Underlined)

1. Check flying controls for free movement.
2. Cowl flops - Up
3. Wing flaps - Down 1/4 to 1/2 required.
4. Remove landing gear control lack and cock safety
        lock - removed and locked.
5. Supercharger - Low.
6. Oil Cooler shutters - Up - Except during cold weather.
7. Carburetor air - Up.
8. hydraulic pressure - 750 - 950 lbs./sq. in.
9. Booster pumps -On
10. Nose and main gear emergency control - Up.
11. Mixture Control - Auto rich.
12. Propeller Controls - high RPM
13. Propeller Switches - Automatic, Safety, Normal.
14. Batteries - On.
15. Main Inverter - On.
16. Generator main line switches. 0n.
17. Fuel Supply - Adequate.
18. Tabs - (As required).
19. Hatches - closed and satisfied.
20. Crew - In position.
Title: Re: "Superchargers low and latched"
Post by: cpxxx on June 06, 2011, 03:55:50 AM
Actually a quick Google for a B25 checklist revealed that one of the steps is 'Supercharger low and locked'.  Which is similar to latched, I suppose. But it's actually part of the landing checklist. Typical Hollywood!
Title: Re: "Superchargers low and latched"
Post by: Shuffler on June 06, 2011, 11:49:16 AM
That pearl harbor movie was all very factual :)


























 :rofl
Title: Re: "Superchargers low and latched"
Post by: icepac on June 06, 2011, 11:51:52 AM
I'm sure intrepid or stupid pilot took one off using high supercharger and managed manifold pressure with the throttles to get shorter roll.
Title: Re: "Superchargers low and latched"
Post by: MachFly on June 06, 2011, 03:16:30 PM
Actually a quick Google for a B25 checklist revealed that one of the steps is 'Supercharger low and locked'.  Which is similar to latched, I suppose. But it's actually part of the landing checklist. Typical Hollywood!

So what does "locked" have to do with a supercharger? Since you mentioned it's from a landing checklist, "locked" would be used for "landing gear down and locked", but that has nothing to do with a supercharger.
Title: Re: "Superchargers low and latched"
Post by: Stoney on June 06, 2011, 03:22:46 PM
So what does "locked" have to do with a supercharger? Since you mentioned it's from a landing checklist, "locked" would be used for "landing gear down and locked", but that has nothing to do with a supercharger.

Could be the boost control lever had some sort of mechanical lock on it to keep it from being inadvertently moved during throttle or prop lever operation.  There are some guys on this board that have B-25 time in real life.  I'm sure they can chime in.
Title: Re: "Superchargers low and latched"
Post by: Shuffler on June 06, 2011, 03:24:40 PM
...or reference to all the way low.

Title: Re: "Superchargers low and latched"
Post by: MachFly on June 06, 2011, 03:27:50 PM
Could be the boost control lever had some sort of mechanical lock on it to keep it from being inadvertently moved during throttle or prop lever operation.  There are some guys on this board that have B-25 time in real life.  I'm sure they can chime in.

I doubt it, you don't normally have locks on power levels, that's because when you want to move them fast you don't want to have to deal with any locks. Before the flight you would normally set how tight you want them to be.
Title: Re: "Superchargers low and latched"
Post by: Babalonian on June 06, 2011, 03:46:28 PM
I believe the proper term with superchargers is that they've "engaged", much like you engage your various gears while shifting with a manual transmition.
Title: Re: "Superchargers low and latched"
Post by: colmbo on June 06, 2011, 04:06:44 PM
I doubt it, you don't normally have locks on power levels, that's because when you want to move them fast you don't want to have to deal with any locks. Before the flight you would normally set how tight you want them to be.

Machfly, how much time do you have in WWII era aircraft?  Things were done differently then.

That checklist also says the reply is "up" for the cowl flaps which I'm guessing refers to the cockpit control position vs the cowl  flap which would be open, closed or trail.
Title: Re: "Superchargers low and latched"
Post by: Bodhi on June 06, 2011, 05:23:55 PM
Some US aircraft have friction locks on the super charger lever just like the throttle, mixture, and prop.  Not aware of a mechanical lock as most of the past stuff I worked on was without working superchargers. 
Title: Re: "Superchargers low and latched"
Post by: Shifty on June 06, 2011, 06:27:48 PM
That pearl harbor movie was all very factual :)


























 :rofl


Yep... Hammer Down!  :D
Title: Re: "Superchargers low and latched"
Post by: MachFly on June 06, 2011, 07:13:03 PM
double post
Title: Re: "Superchargers low and latched"
Post by: MachFly on June 06, 2011, 07:47:35 PM
Machfly, how much time do you have in WWII era aircraft?  Things were done differently then.

Don't have any time in a WWII aircraft or anything with a supercharger for that matter. I know you have some time in a B-24, any idea what they mean by "latched"? Or is it just some hollywood BS?
Title: Re: "Superchargers low and latched"
Post by: saggs on June 06, 2011, 09:57:23 PM
My best guess (if it was real) would be supercharger controller on the "low" position, with the control lever "latched" via friction lock, or detent, or something.
Title: Re: "Superchargers low and latched"
Post by: F22RaptorDude on June 06, 2011, 10:14:08 PM
I liked that movie, its the only movie I'm taking to camp with me(cause we will have electric power in our tents, I know takes the fun out of camping but whatever) I like the movie Just for it being a movie with a bit of action.

I recall a time when People watched movies to just watch them and enjoy not doing work or something else. Now its all criticism these days  :confused:
Title: Re: "Superchargers low and latched"
Post by: colmbo on June 07, 2011, 01:14:13 AM
Don't have any time in a WWII aircraft or anything with a supercharger for that matter. I know you have some time in a B-24, any idea what they mean by "latched"? Or is it just some hollywood BS?

I would guess that the control is locked in place to prevent unwanted movement.
Title: Re: "Superchargers low and latched"
Post by: Pigslilspaz on June 07, 2011, 02:48:32 AM
I liked that movie, its the only movie I'm taking to camp with me(cause we will have electric power in our tents, I know takes the fun out of camping but whatever) I like the movie Just for it being a movie with a bit of action.

I recall a time when People watched movies to just watch them and enjoy not doing work or something else. Now its all criticism these days  :confused:

I've always been critical of movies ever since high school (took film study for what seemed to be an easy A with movies during class, was wrong and had almost twice as many essays as the next hardest)

However, the one thing I cannot stand above all else in a movie, conversation, book, etc., is historical inaccuracies.
Title: Re: "Superchargers low and latched"
Post by: SFRT - Frenchy on June 07, 2011, 10:59:09 AM
(http://farm5.static.flickr.com/4059/4653748193_d0a2e01c26.jpg)

I bet you that the little tab on the top of the supercharger levers is the ' lock tab'. After all this thing already has a throttle lock, and a mixture lock.

BTW Icepac,  supposely there's no real benefit on using 'high' as the pressure gained is offset by the increase load to run the 'high' setting.