Quickmarch 488 Posted February 16, 2013 Report Share Posted February 16, 2013 I was messing about, pondering my next purchase/lease aircraft for QuikAire. I've been flogging this poor little C172 up and down the Coast (Pacific NW), making a buck here and a buck there. I need more capacity at a good price. I also want something with Amphib capability because there's lots of opportunities around here for picking up work at water bases. Choices: Aerosoft DHC-2 Amphib Beaver Stock FSX G-21 Goose Amphib (I'm not wealthy enough, yet, to talk to Mr. Manzo about his Albatross) Now, I thought that the Goose would be a good choice. Big round engines, two of them, ought to lift a fair load. What a surprise when I imported the Goose into AH! Here's the numbers for the "Bare Metal G21", matched with a set of numbers from a RW Erection & Maintenance Handbook: FSX (As Loaded) MTOW - 9200 Lb FSX (From Kneepad SPECS) - 9200 FSX (W&B) - 9200 RW MTOW - 8000 FSX (As Loaded) Empty Wt. - 6923 Lb FSX (From Kneepad SPECS) - 5425 FSX (W&B) - 6923 RW Empty Weight - 5475 FSX (As Loaded) Useful Load - 2277 Lb FSX (From Kneepad SPECS) - 3775 FSX (W&B) - 2277 RW Useful Load - 2525 FSX (As Loaded) Max Fuel - 340 USG FSX (From Kneepad SPECS) - 200 FSX (W&B) - 323 RW Max Fuel - 220 FSX (As Loaded) Cargo Cap. - 237 Lb - YES! 237 pounds FSX (From Kneepad SPECS) - 2575 FSX (W&B) - 339 RW Cargo Capacity - 1205 Lb FSX (As Loaded) Range (NM) - N/A FSX (From Kneepad SPECS) - 695 FSX (W&B) - N/A RW Range - 1390 NM - 75% @ 5000 ft FSX Fuel Burn/hr - N/A FSX (From Kneepad SPECS) - N/A FSX (W&B) - N/A RW Fuel Burn/hr - 51 USG - 75% @ 5000 ft Looks like I'm going to have to dismantle the .CFG file and re-assemble it with some meaningful numbers. That is, if I decide I want one enough to pay $706,000 for it or cough up $88K + $39K/month to lease the rascal. The old DHC-2 is starting to look pretty good at half the fuel burn and a full half-ton of capacity. YMMV, March Link to post Share on other sites
brett 2,289 Posted February 16, 2013 Report Share Posted February 16, 2013 Have you looked at the default fixerupper for the Goose over at OZX yet March. I think you need this file and this extension file plus there are a bunch of repaints available on the first link. It's pretty sweet. Don't forget to backup the original aircraft folder because it overwrites it. Just got it installed but haven't had a chance to do the full test up yet, just a quick fly. I have no doubts it will be a keeper. JMO Link to post Share on other sites
allardjd 1,853 Posted February 16, 2013 Report Share Posted February 16, 2013 March, There's a pretty good dialog covering the issues with the Grumman Goose here... http://forum.justflight.com/forum_posts.asp?TID=6004&KW=goose#top The basic problem is that with the tanks filled, there's only 237 lbs. of cargo capacity remaining before you bump into MTOW, which AH enforces. It actually isn't much of a problem for you, the human pilot but if you use AI pilots, they must fly with full tanks and so their cargo capacity is abyssmally low. You can tweak the AC before importing it, mainly by lowering the empty weight. I'd suggest either leaving it as is and flying with part tanks or tweaking it to something closer to RW values before importing it into AH. John EDIT: The part about the Goose starts about two posts into the thread and you can ignore the part about wrong fuel type - that was an AH bug and has long since been fixed. JDA Link to post Share on other sites
snowingairlines 0 Posted February 16, 2013 Report Share Posted February 16, 2013 The only problem with the OZx goose, is that is hold even less cargo than the default one. Link to post Share on other sites
Quickmarch 488 Posted February 16, 2013 Author Report Share Posted February 16, 2013 Thanks for the comments, guys. Basically what everyone is saying is that MS screwed the pooch in the .cfg file. The numbers in FSX (and thus in AH) are way far off the published RW figures for the aircraft (and there's not much I can find out there). Take a look at the screenshot from the rigging manual, above. Look at the "Payload Table", bottom of the page. This manual remarks "Normal Fuel Capacity" 175 USG, so it looks like they fudged the range in favour of capacity even when new. However, according to JA, AH is going to use the 220 Gal figure for AI pilots, so we learn to live with it. Quote: 75% @ 5000', 175 USG, 180 Mph (157 Kt), 1205 Lb Payload (with one crew), 580 Mi (504 Nm) Range. Unquote *Note: This manual doesn't specify "units" in the payload table, but I'm using Lbs, Miles, and USG because that's what the manual uses when it DOES specify units. Here's another source: Pacific Coastal Airlines. They actually fly these aircraft in regular service (or, at least, used to). Quote: G21A - Two 335kW (450hp) Pratt & Whitney R985AN6 Wasp nine cylinder piston radial engines driving two blade constant speed propellers. Performance G21A - Max speed 323km/h (175kt), cruising speed 307km/h (166kt). Initial rate of climb 1300ft/min. Service ceiling 22,000ft. Range with max fuel 1285km (695nm). Weights G21A - Empty 2460kg (5425lb), max takeoff 3630kg (8000lb). Unquote I can't be the first guy to question the validity of the FSX numbers. Never mind the AH aspect. Maybe it's just the engineer in me. I don't like it when the numbers don't line up (see the joke thread in MH). Here's my take (in Lb): 8000 MTOW -5425 Empty Weight _____ 2575 Useful load - 170 You MUST have a pilot (fortunately for me, the 93.6 percentile is lighter) - 1320 This is MAX fuel (220 USG X 6.0 Lb) _____ 1085 Cargo (carrying) Capacity - or - 5 average weight male pax. plus a co-pilot and 65 Lb of baggage I'd use the Pacific Coastal (performance) numbers only because they're more recent. For now, let's ignore the fact that the FSX models are all depicted with three blade props, because that's a whole new kettle of fish. Cheers, March PS: If you're interested, keep an eye on this topic. I'm going to tweak the CFG file, test the result, and post the tweaks here. This could be a career. I've not noticed, because they all seem to fly, but there's a few other A/C in the FSX goody-box that have suspect load carrying capabilities. Take a look at the Maule, for starters. Link to post Share on other sites
Quickmarch 488 Posted February 17, 2013 Author Report Share Posted February 17, 2013 Here's the skinny on the CFG file (aircraft.cfg) I've test flown this configuration with co-pilot and five passengers in the forward most seats all at 170 lb + 65 lb of baggage in the aft baggage compartment. It results in a forward CG but well within normal CG limits I've also flown it off the water and back on, performance as expected. I have not checked cruise performance figures nor fuel burn. Below, you'll find the FSX (as the CFG file is written in my version) then the "Change to:" which is the changes I made to the CFG file. Cut and paste the text under "Change to:" over the same lines in your aircraft.cfg file. IF YOU DO THIS - REMEMBER TO COPY YOUR ORIGINAL AIRCRAFT.CFG FILE AND SAVE IT BEFORE YOU EDIT. For those unfamiliar: I'm not going to get into a description of HOW to copy and save this file. That's for a different time. If you don't know how to do this - STOP HERE. FSX - My aircraft.cfg file: [WEIGHT_AND_BALANCE] max_gross_weight = 9200 // (pounds) empty_weight = 6923 // (pounds) Change to: [WEIGHT_AND_BALANCE] max_gross_weight = 8000 // (pounds) empty_weight = 5425 // (pounds) FSX - My aircraft.cfg file: max_number_of_stations = 50 ***not sure what this is all about. Theoretically, you need 12, not 50 You might change this to: max_number_of_stations = 12 FSX - My aircraft.cfg file: station_load.1 = 170, 0.4, 1.3, 0.6 //"Co-Pilot" Weight (lbs), longitudinal, lateral, vertical positions from datum (feet) Change to: (just to get rid of that pesky co-pilot and add 170 lbs to your load capacity) station_load.1 = 0, 0.4, 1.3, 0.6 //"Co-Pilot" Weight (lbs), longitudinal, lateral, vertical positions from datum (feet) FSX - My aircraft.cfg file: [fuel] LeftMain =-2.6, -8.2, 4.1, 170.0, 0.0 //Longitudinal (feet), Lateral (feet), Vertical (feet), Usable(gallons), Unusable (gallons) RightMain =-2.6, 8.2, 4.1, 170.0, 0.0 //Longitudinal (feet), Lateral (feet), Vertical (feet), Usable(gallons), Unusable (gallons) Change to: [fuel] LeftMain =-2.6, -8.2, 4.1, 110.0, 0.0 //Longitudinal (feet), Lateral (feet), Vertical (feet), Usable(gallons), Unusable (gallons) RightMain =-2.6, 8.2, 4.1, 110.0, 0.0 //Longitudinal (feet), Lateral (feet), Vertical (feet), Usable(gallons), Unusable (gallons) That's it! here's some shots of the water takeoff. Loading Data - Note that we're at MTOW with FULL FUEL, Pilot, Co-pilot, 5 Pax and 65 Lbs of Smoked Salmon (1255 Lb). CG is forward, but within limits. Approaching VR On the step Change from boat to airplane Happy Goosing. Cheers, March Link to post Share on other sites
brett 2,289 Posted February 17, 2013 Report Share Posted February 17, 2013 Wow, that was alot of work on your part. I will give it a try and thanks for the new cfg. Link to post Share on other sites
allardjd 1,853 Posted February 17, 2013 Report Share Posted February 17, 2013 Good stuff, March, and nice work... Thanks for sharing that. John Link to post Share on other sites
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