PSA: Eduard 1/48 Bf-109s (F-G) flaps positioning

[Vlad]

I think quite a lot of people here prefer flaps down, but the lack of flaps position choice on Eduard's 1/48 Bf-109 range (F-G) was annoying me. So I decided to try to raise them. Turns out, even though the instructions don't mention it, that the flaps parts are perfectly engineered to fit into the slot at the back of the wing in the "up" position. Just remove the locating stubs and done, no further hacking or sanding required. Same story for the leading edge slats and radiator flaps 🙂 so there you have it, the flaps are poseable, but the instructions don't tell you. I hope that's useful information to someone.

[Tokyo Raider]

Thanks Vlad!  I do have one of these in the stash to build in future.  I will leep this in mind and make one flaps up...

[Jamie @ Sovereign Hobbies]

8 hours ago, Vlad said:

the flaps parts are perfectly engineered to fit into the slot at the back of the wing in the "up" position. Just remove the locating stubs and done, no further hacking or sanding required. Same story for the leading edge slats and radiator flaps 🙂 so there you have it, the flaps are poseable, but the instructions don't tell you. I hope that's useful information to someone.

 

Hi Vlad,

 

As much as I like Eduard kits, they do seem to premise that everyone prefers to build models with everything hanging open or down. I noticed the very same thing and solution that you note though on my ongoing Hispano Buchon build using a 1/48 Eduard Bf109G-2 as the basis. Every image I could find of the Battle of Britain movie aircraft parked on the ground or indeed of preserved Buchons since shows them parked with flaps up, so I was driven the same way as you to experiment. Similarly, the flaps fit just fine in the up position if the tabs are trimmed off.

[Vlad]

4 hours ago, Jamie @ Sovereign Hobbies said:

 

Hi Vlad,

 

As much as I like Eduard kits, they do seem to premise that everyone prefers to build models with everything hanging open or down. I noticed the very same thing and solution that you note though on my ongoing Hispano Buchon build using a 1/48 Eduard Bf109G-2 as the basis. Every image I could find of the Battle of Britain movie aircraft parked on the ground or indeed of preserved Buchons since shows them parked with flaps up, so I was driven the same way as you to experiment. Similarly, the flaps fit just fine in the up position if the tabs are trimmed off.

 

The 109G kits don't have anything else open or hanging, but I'm aware from reading reviews that the 109Es and 1/48 Fw 190s have worse issues with things not fitting properly if you want to close them up. The actual engineering of the Eduard 109G kits is much simpler than e.g. the Zvezda with its open engine option, so I won't knock Eduard too badly for this one. I really like these kits as well but I've chalked up quite a list of small annoyances with them.

 

Anyway, it's perplexing that they engineered it like that and just don't tell you. All it would have taken is a small insert diagram on one of the instruction pages.

 

As for flap preference, some aircraft have genuine physical/mechanical reasons why the flaps are down when parked (Mustangs most notably). Bf 109s do not, and as you have observed the flaps tend to be wound back up when the aircraft is parked. I'm happy for kits to provide the option but I don't really like the "down" look from forward qurater viewing angles 🙂

Edited January 24, 2021 by Vlad

[Work In Progress]

45 minutes ago, Vlad said:

some aircraft have genuine physical/mechanical reasons why the flaps are down when parked (Spitfires and Mustangs most notably)

Not Spitfires!!

[Vlad]

3 minutes ago, Work In Progress said:

Not Spitfires!!

 

Really?! I thought they needed the pneumatic system pressured, or do I have that backwards?

[Work In Progress]

You have it backwards. It is INCREDIBLY rare to see a Spitfire switched off with the flaps down - maintenance scenarios only. Go look for yourself if you like...

[Vlad]

Just now, Work In Progress said:

You have it backwards. It is INCREDIBLY rare to see a Spitfire switched off with the flaps down - maintenance scenarios only. Go look for yourself if you like...

I stand corrected and enlightened, and have duly edited my post. I'm sure I have seen models where people pose them open, I guess this is just another "showing off the detail" trend that isn't actually realistic.

[Work In Progress]

10 minutes ago, Vlad said:

I stand corrected and enlightened, and have duly edited my post. I'm sure I have seen models where people pose them open, I guess this is just another "showing off the detail" trend that isn't actually realistic.

 

Yes, people often like to have panels and hatches and all sorts of things open in circumstances where in real life they would not be. While people are obviously free to make models however they want to, it does sometimes give people the wrong impression about full size aviation.  You DO quite often see deployed flaps at rest on real-life Corsairs, and sometimes Thunderbolts, so those would be better examples to quote.

Edited January 24, 2021 by Work In Progress

[Tokyo Raider]

2 hours ago, Vlad said:

 

The 1/48 Fw 190s have worse issues with things not fitting properly if you want to close them up.

You are correct for the early tooled Eduard Fw190s, in about 2008, but the all new tooled (about 2017) fw190a has been simplified and builds closed up.  I just built one and it was wonderful to assemble!

 

I have also built the Eduard Fw190D, that is based on the 2007 tooling and its a very tough build to close it up.  I closed mine up, it was designed to be open and the wing root gun hatch and cavity is what makes the build tough.

 

I do want to clarify that the ALL NEW TOOLED Fw190A is redone and wonderful.  I expect a similar new tooled Dora some day...  hopefully!

[Duncan B]

I'm not a huge fan of everything hanging down on models, it's just more for me to knock off. I knew about the flaps being able to be positioned closed by trimming the tabs off but didn't realise the instructions didn't mention it! The lower radiator flaps would droop on the 109G onwards and that's the way I usually pose them but they are prime targets for my clumsy thumbs so usually stay off until the build is just about completed. 

 

Other candidates for always having the flaps up (unless for maintenance) are the EE Lightning and Hawker Hunter, leaving them down on shutdown would cost the RAF Pilot a crate of beer.

 

Duncan B

[fastterry]

I read somewhere that another reason for having the flaps up on Hurricanes and Spitfires was because if one forgot to check their position it was virtually impossible to take off with them down. I think it was from an article in Aviation News by A.L.M.Kennaugh from when he was a trainee pilot and was doing circuits and bumps at night in a Hurricane and forgot to raise the flaps after a bump and nearly didn't make it back into the air. Imagine a scramble if someone forgot to raise the flaps in your assigned aircraft.

TRF

Edited January 25, 2021 by fastterry
getting the pilots name right

[Work In Progress]

Well, it will take off, you've got at least enough power to get off the ground and climb away, but in a siginificantly blunted fashion. It is the rejected landing case, after all, and you don't raise the flaps in that case until you are back up to at least 200 feet to accommodate the sink when you do whip them up as the two-position pneumatic type favoured by British and Russian designers can't be milked up slowly or in stages.

 

If you want a really marginal take-off try a touch-and-go in a Cessna 150 with full flap and carb heat still selected on a hot day. That is VERY likely to put you in the trees at the far boundary.

[Vlad]

2 hours ago, Duncan B said:

I'm not a huge fan of everything hanging down on models, it's just more for me to knock off. I knew about the flaps being able to be positioned closed by trimming the tabs off but didn't realise the instructions didn't mention it! The lower radiator flaps would droop on the 109G onwards and that's the way I usually pose them but they are prime targets for my clumsy thumbs so usually stay off until the build is just about completed. 

 

Other candidates for always having the flaps up (unless for maintenance) are the EE Lightning and Hawker Hunter, leaving them down on shutdown would cost the RAF Pilot a crate of beer.

 

Duncan B

 

Haha, I like those kinds of stories. Is that because they could be damaged or cause unnecessary wear if they were left down for long periods of time on a shut-down aircraft?

 

And how do you cope with the aileron mass balances on Bf 109s? 🤣

 

I don't think there's a mechanical reason for the lower radiator flaps on 109Gs to droop, there are plenty of pictures of parked ones with them fully closed. The main thing to remember with 109 radiator flaps is that they open symmetrically either side of the main flap position. So a flaps up 109 with fully open radiator flaps should not have the lower flap "drooped" all the way to its lowest possible position, and the upper radiator flap should be raised as well. Like this:

 

[Graham Boak]

1 hour ago, Work In Progress said:

Well, it will take off, you've got at least enough power to get off the ground and climb away, but in a significantly blunted fashion. 

You start the rejected landing at a fair speed.  The problem with take-off is not that you can't fly but the distance required to reach flying speed when flaps are extended.  Just like your Cessna.

[Work In Progress]

 

58 minutes ago, Graham Boak said:

You start the rejected landing at a fair speed.

But also, in many cases, a long way down the runway, especially if the reason for going around is excessive speed and height, or a late change in wind direction meaning that your into-wind approach now has a quartering tailwind.

 

Whatever, the fact is that you can take off and climb away perfectly easily in a Spitfire or Hurricane with the flaps down. The main hazard you run in a Spitfire is overheating the engine due to the flap partially restricting airflow through the radiator.

 

It's pretty much an academic question except in a touch-and-go anyway in a Spitfire as you would have to have lowered the flaps on purpose since leaving dispersal, and done your prop and mag checks that way, and that's really hard to do as the temps would be going through the roof. It's also an error of commission rather than a much more easily committed error of omission.

Edited January 25, 2021 by Work In Progress

[Work In Progress]

 

1 hour ago, Graham Boak said:

The problem with take-off is not that you can't fly but the distance required to reach flying speed when flaps are extended.  Just like your Cessna.

 

No, the problem with a Cessna 150 with full flap at max gross is not so much distance required to gain speed but that its rate of climb is utterly pitiful and in some cases (hot day, carb heat still applied) actually non-existent. It will come off the ground and float along in ground effect but not climb out. One of the reasons why they restricted flap travel on later developments, and the second act after applying cold air / full throttle on a go-around is to select flaps 30.

 

Mind you, it didn't help that the 150 and 152 were routinely operated over max gross weight by so many operators, simply because the useful load is so restricted. They were inexpensive and reliable when new but never much cop IMO. 

Edited January 25, 2021 by Work In Progress

[Graham Boak]

14 minutes ago, Work In Progress said:

 It will come off the ground and float along in ground effect but not climb out.

I recall a Jaguar doing that at Warton, when Pete Ginger tried the new high incidence take-off.  The problem lay, we eventually discovered, in the performance prediction programme not allowing for the actual extension of the undercarriage legs in ground effect.  We added a few knots to the predicted rotation speed and when reaching full undercarriage extension and climb-away incidence she was still accelerating and climbed away cleanly.  Not exactly dramatically, but predictably and safely.  It added a few metres to the predicted ground roll.

[dov]

Hallo

Again to he topic:

Bf-109s (F-G) flaps positioning:

Well, best of all, as you say, try to build flaps in a neutral position. This is fine. But please consider, that slats are spring loaded, and open up at ground speed zero.

The flaps and ailerons: Look at FalkeEins

 

http://falkeeins.blogspot.com/search/label/Bf 109

 

Look at all pictures of 109! You can tell yourself what you see!

Not to forget once again: Slats open!

 

Happy modelling

[Work In Progress]

No. 109 slats are not spring-loaded, they are entirely free-floating and are positioned by the airflow over the wing (or by someone pulling them out or pushing them back by hand on the ground - there is usually enough static friction for them to stay put where you leave them until you start the engine or there's a strong gust of wind, or you taxi over a lumpy tussock of grass)

Edited January 27, 2021 by Work In Progress

[Duncan B]

15 hours ago, Work In Progress said:

No. 109 slats are not spring-loaded, they are entirely free-floating and are positioned by the airflow over the wing (or by someone pulling them out or pushing them back by hand on the ground - there is usually enough static friction for them to stay put where you leave them until you start the engine or there's a strong gust of wind, or you taxi over a lumpy tussock of grass)

Agreed and you can find examples where the ground crew have pushed the aircraft back and the slats are closed (or even one open and one closed depending on who pushed where). Personally, in 1/72 scale I'm happy to leave them closed, in 1/48 I will pose them however I feel at the time.

 

Duncan B

[Work In Progress]

If anyone wants a good detailed illustrated overview of the slats and their operation on the 109 (equally applies to the 110 and many other BF types) there's one here

http://109lair.hobbyvista.com/techref/systems/control/slats/slats.htm

[dov]

Well, thank you all, learned something more about this detail!

Happy modelling

[Johnson]

On 1/25/2021 at 11:23 AM, Vlad said:

The main thing to remember with 109 radiator flaps is that they open symmetrically either side of the main flap position. So a flaps up 109 with fully open radiator flaps should not have the lower flap "drooped" all the way to its lowest possible position, and the upper radiator flap should be raised as well.

 

So if the main flaps are down, the radiator flaps are also down?

 

 

[Vlad]

2 hours ago, Johnson said:

 

So if the main flaps are down, the radiator flaps are also down?

 

Exactly. In that picture you posted, the radiator flaps are closed, the gap between them is very narrow. But they're down because the main flaps are.

 

This is what it looks like when the radiator flaps are open with the main flap down. They're spread wide apart either side of the main flap position.