Blackhorse Heinkel He 111

[Cliff Bastow]

I arrived home from work last night to find a huge box standing in my hall.

The HE 111 I ordered from Kings Lynn Models had arrived!

First impressions are good, lovely looking model and the build quality looks nice.

So I am wondering if anybody has any experience of this model and any helpful advice.

I am going the electric route.

Cheers Cliff

[Jon H]

A friend has one with twin 46 strokes. Sounds lovely but is a handful to fly as the wing is not very lifty and the thrust line of the engines is wrong causing large pitch changes with power. We have lowered the flaps and ailerons a few degrees to help the wing do some lifting. All that said it looks super in the air and if you treat it like a bomber it's ok. Just don't be expecting more as it won't appreciate it

[Cliff Bastow]

Hi Jon,

Thanks for that, I assume you mean 46 4 strokes? I would think 46 2 strokes would be too powerful and heavy for this model. I am going the electric route so hopefully model will be a bit lighter and also it would be easy to alter thrust lines. Does it need more down thrust do you think?

Many thanks Cliff.

Edited By Cliff Bastow on 30/04/2017 09:01:45

Edited By Cliff Bastow on 30/04/2017 09:25:08

[Jon H]

Yes I typed that on my phone and the autocorrect went mad. I hate my phone, it's not smart at all.

Anyway, the 4 strokes overpower it and need a great deal more downthrust. You might want to test fly it without the cowls, adjust the thrust lines and then fit the cowls. As for weight I doubt you will save much, his little Enya engines are pretty light

[Cliff Bastow]

Ok Jon, many thanks.

[Jon H]

No worries. Its a great looking model in the air

[Trevor Crook]

Don't just stand there, get one up!

[Jon H]

Way ahead of you

[Trevor Crook]

Cliff, that's good advice from Jon above regarding the thrust lines. I've no experience of the Heinkel, but I do have the BH Mosquito. This is 63" wingspan and weighs about 6lb - don't know how that compares with the Heinkel.

Of course, they are very different machines. The Mossie flies using 2x4000mAh 3s packs, one per motor, each side pulling 450W, giving about 150W/lb. The Heinkel should be fine on a lower power/weight ratio.

To make your take-off runs easier, you could have the motors running in opposite directions to remove the torque effect. Very simple to arrange with EP, provided you can get the reverse pitch props. EP also makes it easier to accomodate the retracts, as you don't have to squeeze tanks into the nacelles. I'm assuming the batteries go in the fuselage like the Mosquito. The Mossie's nose pulls off for access - how does it work with the Heinkel?

[Cliff Bastow]

Hi Trevor,

The batteries go in the fuselage just in front of the spar through a large hatch in the top.

I had already thought about running the motors in opposite directions.

The strange thing is I have two manuals for this model, one downloaded from the internet and one which came with the kitl and they give different recommendations for motors, esc and props! Confused? yes me too. I assume the instructions have been updated but which is the newest version is anybodys guess!

[Janos Deak]

Hello Guys,

I am about to order one of these birds. I need some info please:

- what is the diameter of the OEM spinner?

- what would be the wheel size if I want to go close to scale?

- 2x600W motors with 10x6x3 props will be enough? What do you think?

Thanks

Janos

[Janos Deak]

I have a set of 100mm (4" scale wheels I am planning to use - would this fit?

[Rob Ashley]

Hi Cliff, All,

I have bought a BH He111 and it will be my first EP model - gulp!. I have bought 2 motors (Quantum 36 IIs), 2 ESCs (40 Amp) as I followed the setup recommendation on the motor box, but no props yet. I have run through some calculations and figured that at MAUM of 7.7lb I would need 693 Watts at 90 Watts per lb. As there are 2 motors I assume I can divide by 2 to get the single motor wattage???

That gives me 347 Watts. On a 3s battery the max current draw would be 31.5 Amps with 20% spare capacity totalling 39.38 Amps. So the ESCs should be ok with a 3s setup.

The Quantum 36 motors are 900 kv and I was thinking of 10x5 props. The model IC setup would be 2 x 0.25s which would run on 9x6 props. I have a watt meter to check the setup once I have all the bits, but wouldn't mind a sanity check before I go and buy props and batteries and make smoke..

Any help would be gratefully received.

Best, Rob

[Chris Walby]

Hi, Hope this helps as I have no direct experience of the HE111, but with a couple of BH models, one being a twin.

You have cast your stone so as to speak with the set up you have which will be close as its their recommendation and all should be okay...My advice is keep it as light as you can, that will keep the wing loading down and help all round with take, off, flight and landings.

Looking at the spec you should be using 1200Kv motors so the 900 KV you have are 25% slower, not a problem if you can increase the diameter of the prop (without them hitting anything!) and at worst have to up the pitch.. or I went for 3 blade as they look nicer (but you do loose top speed, I don't mind). I am running a 10x7 on a 920KV motor on 5S at 38A and it produces about a kilo of static thrust for about 570W. If I approximate things back to your set up (e.g. reduce from 5S to 3S (36%) looks like 364W so in the right place!

I think you will be way under with 10x5, if I am using 10x7 and on 5S, can you get away with 11x6 in diameter/pitch?

You are doing the right thing regarding the load testing and best advice is keep the weight down...unless you need to add some to get the C of G, then if the motors/ESC allows go to 4S or 5S as it ups the motor speed, failing that larger capacity lipos.

Let us know how you get on & message me if you need more info on the prop testing

[Jon H]

Rob i would also recommend you go for the largest props you can as the slipstream of the prop over a larger area of wing will give you more lift. Just remember not to cut and glide as it will drop like a stone.

On the IC version my friend is flying we use 12x6 props (if i remember rightly) swinging around at about 9500rpm. This is massive overkill performance wise so do not be concerned if you are seeing less rpm than this. It might be worth giving Richard at warbird replica's a call as his very similar Ju88 would be a good benchmark even if it is a fair bit lighter.

Anything you can do to save weight is well worth doing and i would also recommend deflecting flaps and ailerons down a smidge as well as the wing really needs all the help it can get. Its a shame really as they did a great job otherwise.

Finally i recommend you do all test flying before you cut/fit the cowls as you can make easy thrust line (up/down) adjustments on the fly and test the changes back to back.

[Rob Ashley]

Hi Chaps,

Thanks for the replies - all very useful information. I have checked the motor instruction manual and they can take props ranging from 10x5 to 11x9, with the recommended 36 ic equivalent performance interestingly using a 10x8 prop (the model manual states 25 ic). I think I will buy a couple of sets of props starting with 10x8 and then larger diameter, checking with the watt meter and measuring the static trust each time. I do think I will need to then use 4S batteries. I would like some excess power but not to 'overpower' it.

John - have no fear I am certainly not a 'cut and glide' type - I tend to fly scale aircraft which, as you know, don't like that method and it's not the correct technique. I might also increase the wing incidence by 1deg to start to help with the lift having read your advice.

I guess it is time to order some batteries and props - so far elec is more expensive than IC by far...but I feel I am 'broadening my modelling horizons' to coin a phrase from my father...

Thanks again - Rob

[Jon H]

Sounds good Rob, and it might be worth trying something like 12x6 or 7 and seeing what the watts are doing. If they are under control then the larger dia might help you out.

i am not sure if you can change the incidence given the design and fit of the wings but it might be worth a try

[Rob Ashley]

Hi Jon - helpful as always.

Not sure why but my first post disappeared, so here I go again. After I sent that last post I realised what I had said. You are quite right and attempting to alter the wing incidence on a model whose wings attach to the side of the fuselage would be quite challenging - so I will take your advice about the flaps and ailerons and make life a little easier....

I think a 4s battery is the better way to go if I am going to try and swing larger props such as the 12x6. And this being my first foray into 'leccy I will try to stay safe. I have been looking at a few prop suppliers but they are not being that helpful, does a pusher prop mean it can be used as a tractor but turning in the opposite direction? I was going to go the whole hog and have contra rotating props (thus utilising all the benefits of electric), but am finding it challenging to find the right item. That, coupled with the fact I don't really know what I am doing!!!

[Cliff Bastow]

Hi Rob,

You are quite correct in that you could use a pusher prop rotating the opposite way. I considered doing this myself. The problem is the spinners as supplied they are ready cut for standard props.

As for altering the wing incidence I think this would be difficult with the way they fit into the fuselage. Have you considered setting the flaps a couple of degrees down when up as this would have the same effect?

The power set up I am going to use is one recommended to me by 4 Max but Iam a little concerned as the props are only 9 x 4.5 and I think too much of them will be covered by the spinners.

How have you managed with the CG as I am finding it difficult to get it far enough forward. It seems very tail heavy to me at the minute so I am moving things about to try and reduce the amount of nose weight needed.

Edited By Cliff Bastow on 02/08/2017 19:15:52

[Rob Ashley]

Cliff,

Definitely yes to changing the flaps by a deg or two and not the incident angle. I realised quite soon after I sent that post that changing the wing incidence on this model would be quite difficult - so I won't be doing that.....

What is the setup from 4max you are using? My setup was based on the IC requirements (2 x 0.25s) and I chatted to my mate in the local model shop who recommended the RIPMAX Quantum motors to get a better performance. Jon and Chris (in this thread) have offered advice to increase the prop diameter as much as possible. I am still looking for props at the mo and am likely to buy a few different ones and test them all, having taken their advice.

As for the CG - I am not that far enough forward in the assembly yet so I don't know - sorry. I am changing the UC to a more scale like twin oleo setup before I continue. This will also give me more time to figure out the 'leccy setup.

As for the spinners - they may not be a problem as most of the thrust comes from the outer third of the prop (i.e. 1/3 of diameter inboard from the tip). Interestingly some full size manufacturers like to tell you their props are 90% efficient with around 65-80% of that coming from the outer 1/3.

Some of my WW1 1/4 scale jobs (with a Zenoah 23cc) only have 1/3 of the prop diameter outboard of the of the cowl and they produce significantly thrust than required.

[Cliff Bastow]

Hi Rob,

Thanks for the info about props, I am feeling a bit better about them now. The set up I am using is as follows, 4 max own motors no PO 3535-1090. 45 amp speed controllers and 9 x 4.5 props.

4 Max state this will give about 3.5 lbs static thrust each. An unusual way to state power to me and not sure what that actually means?

They state they will give more power than the recommended OS motors with a top speed of about 50 MPH with cruise at about 1/2 to 2/3rds throttle and 8 minutes flight time.

[Jon H]

i woudnt get too worried about contra rotating props. it sounds clever in theory but has little practical advantage. in the case of the 111 its not even scale!

[Former Member]

[This posting has been removed]

[Rob Ashley]

Cliff,

As 4Max know infinitely more about E power than me I guess their setup will work well. I note your motors have a kv of 1090 where as mine are slower at 900kv. Are you running on a 3s battery? I am going to use 4s.

Static thrust is the amount of thrust you get from the power train without the model moving forward (so no air moving into the prop). This differs to the in-flight (dynamic) thrust due to the airflow moving into the propeller (due to forward motion) and thus increasing prop drag, so dynamic thrust reduces with forward speed. It is hard to measure without a wind tunnel. At max speed the net dynamic thrust equals zero. Static thrust values will give you an idea of the weight each motor setup will pull forward.

Jon, Tom, I can't seem to find too many sizes that have a contra rotating prop anyhow. Just thought this electric lark was worth a go to try that method. As it is, I think you are right and 2 x conventional rotating props will not make too much difference to the not really scale model. Failing that there are 3 blade versions from 4 max but I need to do some testing once the props have arrived, before I end up buying a full compliment of props I don't need.

[Cliff Bastow]

Robb,

I have just realized I have messed up! I was going to run on 3s batteries as all my other models run on 3s and I did not want yet another size! however on rereading the recommendation from 4 Max I now notice that it was for a 4s set up! Blast it lol.

I guess I will now have to bite the bullet and buy some batteries. More expense! I don't know how I will explain this to the better half! lol