They're out there among us...

[Rich]

Found on Facebook. Comments in response to question on NG load carrying ability.

[astaib]

let's wait for an inspector to read this!

[Boatguy]

It's all fun until the day it's not and the survivors find out the insurance is cancelled.

[mhoran]

How unfortunate. My co-owner and I learned about the importance of weight and balance early in our training, when our instructor crashed an overweight DA20 on a 100 degree summer day on takeoff. Our instructor didn't make it, but his student survived. Ever since we've both been extremely cautious about load and the impact of density altitude. It's no joke.

[Mjwatlanta]

An interesting feature of the DA40 that I think is too often misunderstood or ignored is maximum zero fuel weight. In most planes, a reduction in fuel weight allows for a pound for pound increase in passenger weight. Not true in a Diamond. In a DA40 you can pretty much empty the tanks and not get much of an increase in the 580 pound (for my plane) load limit. I’ve done all kinds of load shifts and manipulations on Foreflight, and there is simply not much we can do to up our passenger weight limit by more than a few pounds. This stuff matters.

[Steve]

How unfortunate. My co-owner and I learned about the importance of weight and balance early in our training, when our instructor crashed an overweight DA20 on a 100 degree summer day on takeoff. Our instructor didn't make it, but his student survived. Ever since we've both been extremely cautious about load and the impact of density altitude. It's no joke.

It seems that ignoring W&B is a fairly common issue, even among experienced pilots. About 10 or twelve years ago a friend who is an airline pilot asked me to help one of his coworker's sons who was trying to get into the Marines as an aviator. There was some (relatively minor) medical issue holding up his acceptance. I was a Reserve Navy Flight Surgeon back then, and had a lot of contacts at NAMI, so I called around and was able to give him the advice he needed to get approved.

Fast forward a couple of years - he was flying (C130s I think) and was home on leave with few friends. His Dad owned a 172 (that the Marine had flown before numerous times). Took his friends up flying on a hot day and crashed and burned. They were a couple of hundred pounds over Max Gross, and the CG was well aft of the limit.

Every time I see my airline pilot friend (we had dinner with him and his wife last night), he relates how appreciative his coworker was (and is) that I helped get his son into flight training in the Navy. But I always feel a bit queasy about the whole episode. Not guilty, but weird.

At any rate, I have always been very careful about W&B. When the kids were still living at home I've flown a couple of pounds below Max Gross in my airplane, but never even close to CG limits. Even now, flying solo or with one other, I always do the W&B on Foreflight for every flight even though it would be impossible to be outside of the limits. I like adjusting my approach speed based on Gross Weight...

[Chris]

Fast forward a couple of years - he was flying (C130s I think) and was home on leave with few friends. His Dad owned a 172 (that the Marine had flown before numerous times). Took his friends up flying on a hot day and crashed and burned. They were a couple of hundred pounds over Max Gross, and the CG was well aft of the limit.

...

At any rate, I have always been very careful about W&B. When the kids were still living at home I've flown a couple of pounds below Max Gross in my airplane, but never even close to CG limits. Even now, flying solo or with one other, I always do the W&B on Foreflight for every flight even though it would be impossible to be outside of the limits. I like adjusting my approach speed based on Gross Weight...

Such a sad story. These days it's so easy to enter W&B into Foreflight, Garmin Pilot, or even a simple spreadsheet that there's no excuse for not knowing your W&B within a few pounds. It just takes discipline to avoid the "well we made it OK last time so let's go for it" mindset. I always try to imagine what the NTSB report (and "CrashTalk" discussion) would look like in order to prevent myself from slacking off on this.

[Rich]

An interesting feature of the DA40 that I think is too often misunderstood or ignored is maximum zero fuel weight. In most planes, a reduction in fuel weight allows for a pound for pound increase in passenger weight. Not true in a Diamond. In a DA40 you can pretty much empty the tanks and not get much of an increase in the 580 pound (for my plane) load limit. I’ve done all kinds of load shifts and manipulations on Foreflight, and there is simply not much we can do to up our passenger weight limit by more than a few pounds. This stuff matters.

in the Lyc version, the difference (when it exists) is 111 lb, or 18 gallons of fuel. that's about my minimum for initiating a flight, anyway.

In the NG it's a little harder to tell, but commonly it looks like 101 lb. That'd be like 15 gallons?

Of course loading passengers up to MTOW makes for the most safety, since you'd have zero fuel and aren't going anywhere

The NG also has something weird - a minimum flight mass of 2072 lb. It would seem to be almost impossible to violate that limitation.

[Mjwatlanta]

Rich,
I’m confused. I think you write that I can reduce my fuel by 15 gallons and increase my passenger/luggage load by 101 pounds. That would be 680 pounds. Fiddling with Foreflight I can go to zero fuel and that very much exceeds the ZFW. Now, there is a very real chance I’m doing this wrong, but with full tanks (39) I can carry 580 pounds. With empty tanks I can do 585. ZFW is the limiting factor - not gross weight.

I had a long talk with my instrument DPE about this. He taught me about how this ZFW relates to the wing’s ability to support the fuselage.

I hope I’m confused. But every manipulation still results in a red ZFW warning at the top of the page. See attached. At 590 and 0 fuel I’m in w&b but exceed zfw. At 585 and full tanks I’m in w&b but at limit. At 580 with full tanks I feel good about it. Am I wrong?

[dant]

In the AFM landing overweight is just a "land lightly" warning which isn't anywhere near as bad as take off or CG issues, so while I note that limitation I'm not overly stressed about it. IIRC Alaska flying has a carte blanche "take off with +10% MTOW" allowance which has always bothered me - I tend to run cautious on that front but not as cautious as I am about CG. CG is no joke.

That being said, I suspect there's a population of DA40 50g pilots who use the 40g rear CG limits. The 50g rear CG limit is... close.