Excellent advice, thanks!
You’re welcome, Snoopy. I also have a fix for the nose gear issue (whereby the gear points all over the place and remains therein flight). It is a minor modification to the nose gear fairing, add a “shark fin” to it. I tried that back in 2015 and it was very effective.
Do you have pictures by chance of the airvent mod?
On page 5 of this thread you have a photo and the relevant summary with noise level in dB.
In a nutshell: tape the upper half, test and if happy, REMOVE and replace with a solid plug ;-)
https://www.diamondaviators.net/forum/viewtopic.php?f=8&t=4600&hilit=noisy&start=40
In case above image goes dead:
With all vents closed the measured sound level at ear level was 100 dB (C weighting) at 2400 RPM, same as last time (good – consistent baseline).
Before the flight I had taped the lower half of the pilot’s NACA vent using clear duct tape. I cut a 3/4 inch thick piece of open cell foam and placed it in the duct behind the copilot vent.
With the pilot’s vent open, the noise level was 101.5 dB, air flow was 10 m/sec.
With copilot’s vent open, the noise level was 105 dB, air flow was 4.1 m/sec.
So, like the original BLOG poster of taping the vent, I saw a significant noise reduction (101.5 dB vs 105 dB), with only a small reduction in air flow (10 m/sec vs 12 m/sec). The noise quality was also “better” with (to my ear) most of the reduction being in the higher frequencies. The foam installation was ineffective in reducing noise (no change in noise level) and cut air flow by 2/3.
Very odd that Diamond hasn’t made a fix for this. What is the noise? Is it just “vent noise” or is it modulated by the propeller?
It is vent noise but a howl from horror. It’s haunting. In summer it’s a real pity, either a quiet or cool ride. Very happy to learn about the tape fix!
Either it’s me but seems nobody mentioned what I consider the most annoying thing with a DA40 in my experience…it is nose heavy.
With 2 POB you will need some weight in the back to get it in the envelope, especially with G1000.
Probably does not apply so much für the Lyco versions, which were originally the subject.
jfw wrote:
Either it’s me but seems nobody mentioned what I consider the most annoying thing with a DA40 in my experience…it is nose heavy.
You mean on landing? takeoff? or in general when pitching/trimming?
I did not notice much of that in most of my WnB configs