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Scale Free Flight Forum => Scale, Indoor (F4D, F4E, Kitscale) => Topic started by: André Wind on Jan 31, 2026, 06:23 PM

Title: Airco DH2
Post by: André Wind on Jan 31, 2026, 06:23 PM
I'm building this model from a plan that I've reduced to 1:16 with a wingspan of 57cm
The engine that I'm going to use is a GM120.
Is there someone who can give an advice about the up and site trust?
Title: Re: Airco DH2
Post by: nickhawk on Jan 31, 2026, 06:33 PM
Welcome Andre, I like the DH2 and it is definately in my future plans. I hope that the "sparkie " will be powerfull enough for a decent flight...   :)
Title: Re: Airco DH2
Post by: g_kandylakis on Jan 31, 2026, 07:15 PM
Hi Andre,

looking very nice and quite interesting.

Regarding thrustlines on a pusher, have a look at this:

https://hpa.aeromodelling.gr/index.php?topic=159.0
Title: Re: Airco DH2
Post by: André Wind on Jan 31, 2026, 08:45 PM
Thanks Georg,

The thread is very helpful.
Title: Re: Airco DH2
Post by: Stunthenk on Jan 31, 2026, 11:17 PM
The interesting thing about this subject is that every side-view or pictures of a fullsize airplane I've ever seen shows a massive amount of downthrust on a pusher engine (which is actually upthrust when converted to a tractor engine in the same position). But every model built shown so far has a perfectly straight engine, either originally or after trimming flights. Anyone understand this?
Title: Re: Airco DH2
Post by: OZPAF on Feb 01, 2026, 12:56 AM
I suspect that the drag of the fuselage is proportionally much higher at the lower flying speed of the models, moving the centre of drag closer to the thrust line.

John
Title: Re: Airco DH2
Post by: André Wind on Feb 03, 2026, 08:01 AM
Tryout if everything is lined up correctly.
The struts are connected with small pieces of PLA that I've drawn in SolidWorks and printed.IMG_20260202_204056_HDR.jpg
Title: Re: Airco DH2
Post by: billdennis747 on Feb 03, 2026, 11:20 AM
Reply to stunthenk (are we unable to reply to individual messages?)
I built a diesel FF FE8 and it specified, and needed, no offsets at all. Reminds me of my 0/400 with tractor engines also close to CG which also needed none.
Title: Re: Airco DH2
Post by: André Wind on Feb 04, 2026, 02:20 PM
One size fits all  8)
GM120
Title: Re: Airco DH2
Post by: André Wind on Feb 07, 2026, 09:10 PM
Wings covered tissue and only sprayed with water.
Title: Re: Airco DH2
Post by: André Wind on Feb 14, 2026, 05:45 PM
Printed a few parts with one layer and 5% infil.
Title: Re: Airco DH2
Post by: André Wind on Mar 10, 2026, 07:42 PM
Still a lot to be done, but.....
Title: Re: Airco DH2
Post by: dputt7 on Mar 11, 2026, 02:06 AM
Nice work, well done!
Title: Re: Airco DH2
Post by: André Wind on Apr 08, 2026, 11:02 AM

The last parts are drying after a treatment with dope and the last step is to paint them in the right color.
Title: Re: Airco DH2
Post by: g_kandylakis on Apr 08, 2026, 08:06 PM
Hi Andre,

looks very nice! You could not settle for a simplier model?

George
Title: Re: Airco DH2
Post by: Piecost on Apr 09, 2026, 12:08 AM
Very nice. I particularly like the printed engine. Can you tell me how much it weighs so far?
Title: Re: Airco DH2
Post by: OZPAF on Apr 09, 2026, 03:14 AM
You have a real aircraft factory Andre - turning out precision replicas :)

John
Title: Re: Airco DH2
Post by: André Wind on Apr 10, 2026, 08:38 PM
Quote from: Piecost on Apr 09, 2026, 12:08 AMVery nice. I particularly like the printed engine. Can you tell me how much it weighs so far?
Model weights until now in this state with Horizontal and ruder 104 gram.
Wing loading 9,21 gram/dm²
Title: Re: Airco DH2
Post by: nickhawk on Apr 10, 2026, 11:35 PM
Nice Andre, I hope to see it in Nijmegen next November
Title: Re: Airco DH2
Post by: Piecost on Apr 11, 2026, 01:20 AM
Very Nice!
Title: Re: Airco DH2
Post by: André Wind on Apr 11, 2026, 09:00 AM
Quote from: nickhawk on Apr 10, 2026, 11:35 PMNice Andre, I hope to see it in Nijmegen next November

Hi Nikos,

it was a pleasure meeting you in Wijchen last year and I look forward to meeting you again in November of this year.
Title: Re: Airco DH2
Post by: Skyraider on Apr 14, 2026, 12:27 AM
Awesome build Andre. Following with great interest.

Skyraider