Has anyone noticed that when you open the Saab 340 .acf in Planemaker, the Basic Empty Weight is set unrealistically low?
The setting in Planemaker for BEW is 12,655 lbs. I did a Web search and found a Saab 340A sales brochure listing the average BEW as 18,800 lbs. I also found a Saab 340A for sale listing BEW of 17,615 lbs. The problem with having such a low BEW in planemaker is that it gives the impression the aircraft can take an unrealistically large payload.
Since MZFW = 25,700 lbs
Max Payload = 25,700 - 12,655 = 13,045 lbs! According to the brochure Max Payload is actually closer to 6,900 lbs. So why has the Planemaker BEW been set so low? After some experimentation my best guess is that it is an x-plane "tweak" to allow actual aircraft performance in the sim match the charts.pdf data. I actually modified the .acf, correcting the BEW to 17,615 lbs, but having done so, got nowhere near the performance figures in the book.
So the trick with this aircraft seems to be to accept the fictitious planemaker BEW as a necessary tweak (leave it at 12,655 lbs), but treat that as BEW of 18,000 lbs for planning purposes. So if you add 30 passengers and bags (about 6,900 lbs) and 3000 lbs of fuel, planemaker will report total weight as:
12,655 + 6,900 + 3000 = 22,555 lbs
However the aircraft will actually perform in the sim like:
18,000 + 6,900 + 3000 = 27,900 lbs
I have seen some posts mentioning the Saab barely scraping into FL200 at 100-200 FPM. I got similar results with my modified .acf where BEW was set at the more realistic17,615 lbs and X-Plane Weight & Balance & Fuel reported a "total weight" of 28,000 lbs with 6,900 lbs payload and 3,000 lbs fuel. Going back to the original .acf with the same payload and fuel I got performance very close to what is published in charts.pdf.
So I am documenting my findings here in case it helps anyone new to this outstanding aircraft. Don't add too much payload. When Planemaker reports a total weight of 22,500 lbs, read that as 28,000 lbs and you should not be surprised by bad performance. If anyone has got different results and thinks my findings are incorrect, please add to this thread.