Scale Model Shop

**AlanG** · 01 August 2013, 20:11

Handbooks for the Bf109 can be found here

Bf 109 Manuals and Documents

**Guest** · 01 August 2013, 20:16

Thanks, I'll take a browse

Atb.

**flyjoe180** · 01 August 2013, 23:12

The Bf109 had automatic leading edge slats, these extend naturally on the ground as there is no air pressure to keep them in, until they are pushed back up manually. Automatic slats deploy automatically when the angle of attack increases (negative pressure or the 'lift envelope' moves forward towards the leading edge), energising the boundary layer or air flow over the wing surface. This serves to delay an aerodynamic stall (or loss of lift-producing airflow over an aerofoil), and to increase the effective angle of attack of the wing (by increasing lift coefficient). Another example of automatic slats is the system on the Douglas A-4 Skyhawk. I believe that it was common practice for Luftwaffe ground crew to push the slats in when the aircraft was parked. I think the colour beneath the slat was the wing surface colour. I'm sure Stona or some other Bf109 enthusiast will confirm or otherwise.

See here for some detail into the workings of the slats: The 109 Lair- The Online Source for Messerschmitt 109 information

As for the flaps, they appear to be plain flaps, but split with radiator flaps fitted, the operation which depends on the version. I believe they were manually operated via a linkage controlled by a wheel on the left side of the cockpit wall (unsure whether this was via a cable or chain). They would probably stay up on the ground, as opposed to hydraulic flaps which droop naturally over time as hydraulic pressure is lost. Pictures show the flaps drooped during maintenance however, so I guess it depends how you want to display your model. Again, someone with better knowledge will advise no doubt.

A picture of a 109 flap showing colours on this link:

http://m9.i.pbase.com/o6/72/722972/1/79470009.UWtwEoeF.DSC_3759.jpg

Hope this helps you Colin. You probably are unable, like me, to read German so those manuals in the link from Allyne help but are not easy to use.

**stona** · 02 August 2013, 12:49

There are photos of Bf 109s parked with the flaps in various positions from fully up to fully down, likewise the radiator flaps. Go with whatever you fancy.

As for the slats on the leading edge, it was common practice to push these in on parked aircraft to prevent an debris getting into the mechanism, potentially jamming the slats in or out. On a tail dragger, like the 109, they would stay in. I have seen pictures of parked aircraft with slats out (or even one in one out) but mostly they are in.

An important detail, usually missed by modellers is that when the flaps were wound down the ailerons drooped progressively too. With flaps up the ailerons droop 1.2 degrees which is negligible on a model but with flaps fully down (42.5 degrees) the ailerons have a significant and noticeable droop of 11 degrees.

Joe, the flaps and elevator trim were operated by the two large (30cm) wheels on the port side of the cockpit. The linkages were entirely mechanical. By rotating both wheels together it was possible to lower the flaps and simultaneously adjust trim to compensate for changes caused by the lowering of the flaps. It's a feature that British test pilots at the RAE commented positively on.

Cheers

Steve

Edit: What colour was revealed by the deployment of the slats is a bit like the Spitfire wheel well colour question. The usual answer was that the primer colour RLM 02 would be revealed, which is certainly the case in some examples. However there are plenty of others where the colour in that area is simply a continuation of the upper surface camouflage colours. Unless you have a picture of your subject showing this area your guess is as good as anybody's.

As for the colour inside the slat itself, there is colour film of some early Bf 109 Es which shows this to be the under surface colour, RLM 65. You can go with that, later RLM 76, RLM 02 primer or, on a late war aircraft, just aluminium.

**Guest** · 02 August 2013, 15:44

Thanks for the info guys.

Atb, Colin.

**Guest** · 29 December 2023, 20:19

Originally posted by AlanG

Handbooks for the Bf109 can be found here

Bf 109 Manuals and Documents

I’ve already got them. Plus they should be free - they should be on the public domain free of charge

**Guest** · 29 December 2023, 21:41

They are in the public domain in most countries: they were published over 70 years ago. But “public domain” is not the same as “free” — in fact, it also means that anybody can charge whatever they like for them.

**Ian M** · 30 December 2023, 06:10

Think he found what he needed to know 10 years ago lol,

**adt70hk** · 30 December 2023, 09:33

. Of

Originally posted by Ian M

Think he found what he needed to know 10 years ago lol,

I had noticed that straight away.... But wondered if anyone else would!

**Guest** · 30 December 2023, 10:28

I don’t want to get into semantic wrestling but by public domain I meant free access by the…public!

There are some greedy unscrupulous people out there that charge people for pdfs that have absolutely zero rights to do so.
When I said I have them all I meant the main Bf 109 ‘Handbuch’ but there are still a ton of manuals out there that would serve modellers very well.

Necropost or not it I feel it’s still a valid point

**Scratchbuilder** · 30 December 2023, 11:13

4 pics online showed them in wartime with the flaps down...

**Guest** · 30 December 2023, 18:26