210 HP with IO390. Vote

[Tommy]

No matter how you cut it, an IO-390 is a win win scenario at tbo.

[Paul]

It needs a turbo to be of any interest to me. Sure at TBO why not but I really need performance above 9,000 feet. Anything less and my current 180 hp seems fine.

[Antoine]

I have in the meantime made my opinion. Wait unbtil TBO. This said, if you are looking for more performance at altitude you can look at it that way:

at 5000 ft, we have 850 HPa or 85% power
at 10000 we have 700 HPa or 70% power

adding 17% power by installing the IO390 means we get our previous sea level power until around 6000 ft and still get 82% of our old power at FL100.

Of course that's not quite a turbo, but half way there and with no added complexity, hardly any weight penalty, etc...

[Joey]

What would be great would be to get the extra power, it solves the 17 lbs of ballast in the nose, clean up the cooling if possible, get more climb rate AND get more max weight capability along with a few knots of speed. Now you're heading towards the DA-50 (DA-50 lite?). How about clipping 12" off each tip and add winglets...It's really a docile aircraft and a slightly higher stall speed wouldn't bother me. I'd like to see us be able to put the DA40+/DA50- into a standard hangar without smashing the "anti-smash" lights.

[Antoine]

I'm 100% with you.

The idea of shorter wingspan is however more complex than intuition suggests to avoid a negative impact (!) on aerodynamics (clipping the wing reduces the aspect ratio)
It would only be beneficial if the whole wing were redesigned to preserve the aspect ratio while reducing wing area (so really one would be clipping the inboard part). As a consequence, one would also want to reduce the size of the tail surfaces , which would bring wetted area down. This however is a major engineering project and I cannot see Dioamond even considering it...

However, installing a slightly heavier engine (IO390) and maybe shifting it slightly forward as part of the cowl redesign would allow the CG to be placed far enough forward so that the DA40-180 can pass the spin certification with the NG winglets installed. These should add some fpm while slightly reducing wingspan.
(My understanding is that these winglets were part of the XL design but they caused the plane to fail the spin certification and were removed as a consequence.

Imagine a DA40 XXLS with the winglets, another 150 lbs MTOW increase thanks to the landing gear of the NG, and the 210 HP engine.

It would become a fantastic 145 knot cruiser, a true four-seater and a plane that can easily deal with medium altitude airfields on a hot day.

This project would require a moderate engineering effort and I can even imagine it would fall under the STC category... One for winglets, one for the IO390 engine and one for MTOW...

[Joey]

I'd go for the quick fix of more MTOW and a few extra knots with just the engine swap. Aerodynamic cleanup and winglets could be a step two. Since the DA40's are just 10 years old, how many are up for tbo in the near future? The rate we are flying ousr, it will be 12 years from date of manufacture before we are ready to swap engines. (Our 2008 has 500 hrs on it).

[Rich]

All the talk of extra weight of the engine being beneficial is not applicable to those of us with the older DA40's. It is actually harmful, as these birds have a more forward CG.

[Gary]

All the talk of extra weight of the engine being beneficial is not applicable to those of us with the older DA40's. It is actually harmful, as these birds have a more forward CG.

How much heavier? According to Lycoming, the experimental precursor to the certified engine weighed the same as the IO-360.

At 308 lbs, the engine is rated for 210hp at 2700rpm. Lycoming was able to deliver more horsepower at the same weight and footprint as the successful IO-360, 200hp engine models. http://www.lycoming.com/news-and-events ... ngine.html

If you have a bad forward CG problem like I did (before I lost a lot of weight) there is an OSB-40-21/1 to add 5 kg lead shot to the lower tail-fin. http://www.diamond-air.at/da40-180_sb+M52087573ab0.html

[Tim H]

It's called a DA50.

[Rich]

All the talk of extra weight of the engine being beneficial is not applicable to those of us with the older DA40's. It is actually harmful, as these birds have a more forward CG.

How much heavier? According to Lycoming, the experimental precursor to the certified engine weighed the same as the IO-360.

At 308 lbs, the engine is rated for 210hp at 2700rpm. Lycoming was able to deliver more horsepower at the same weight and footprint as the successful IO-360, 200hp engine models. http://www.lycoming.com/news-and-events ... ngine.html

If you have a bad forward CG problem like I did (before I lost a lot of weight) there is an OSB-40-21/1 to add 5 kg lead shot to the lower tail-fin. http://www.diamond-air.at/da40-180_sb+M52087573ab0.html

Well, lots of posts in here are anticipating that it will weight more. I have no problem with the weight myself (I weight 160 lbs), but others fly it that are more standard-US-male size. Put two of these guys up front and you could have a problem. I refuse to add dead weight just to work around this problem. If the engine weights the same, I'm fine. Just don't want to make it worse. In fact, that's why I still have a MT prop.