dgaad
Posts: 864
Joined: 7/25/2001 From: Hockeytown Status: offline
|
[QUOTE]Originally posted by bobarossa [B]Dgaad, In addition, I was being specific in my post. I specifically said "ferry flights across the Pacific" not cargo flights. I did screw up on the fuel. The C47 normally carried 800 gallons not 500. It also does not specifically say that you can fly only 14 hours with 1600 gallons. He (the flight engineer) states that the extra gas was needed to fly the 14 hours from Fairfield, CA (just northeast of Oakland) to Hawaii (see page 139 of Fire in the Sky by Eric Bergerud). My atlas shows that to be about 2400 miles. No comment on the cargo although at a web site on pilots, it was mentioned that they would carry mail on the ferry flights. Using your range = radius rationale, there would be no need to carry the extra 800 gallons of gas. Your 35 hex normal radius (just over 1000 miles) would almost get you a one-way trip from CA to Hawaii and carrying supplies too. The "hump" flights you mention as an example of the C47's range were from Dinjan in Assam to Kunming, China (see p. 312 of Flying Tigers by Daniel Ford). My atlas shows this distance to be about 550 miles (see map in front of same FT book). They also predominatly used the C-46 since it had better high altitude performance (see above quote of 1200 mile range). Bob [/B][/QUOTE] UV gives 4 ranges for aircraft : Maximum Range Transport Radius Extended Radius Normal Radius Presumeably this means (and the Manual provides some detail here on page 80: Maximum Range : The furthest the aircraft can fly with full tanks and whatever capability was commonly used to extend the flight time. This can only be interpreted as a one way trip. Transport Radius : This has to be a two way transport flight. Many of the level bombers have transport capacities, so this is the radius they use when performing that kind of mission. Extended Radius : The manual is vague, but one can assume this means the maximum round trip radius that an aircraft could make with some combat effectiveness (i.e. reduced bombload or guns only). Normal Radius : again the manual is vague, but we can assume that this would be the radius of an aircraft with no reduction in bombload or, for transports, transport capacity. The manual states that the Maximum Range figure is used to calculate by reduction all of the other figures thus : Maximum Range : z Transport Radius : z times .5 Extended Radius : z times .333 Normal Radius : z times .25 Now, how would this work for the Dakota? All of the above data do give widely varying "range" figures, usually in the 1100 to 2500 miles area. The Boeing site gives a "Maximum Range" figure - of 3800 miles, while this site (http://www.airpower.maxwell.af.mil/almanac/spanish/colombia/c-47a.htm) gives a "maximum range" figure of 2700 miles. Why is there so much variance? 1. Range could vary according to prevailing winds, cruise altitide, type of mission, load, use of onboard jerry can fuel, and a host of other factors. 2. There were a number of Dakota variants. 3. The information contained in these sources is not 100% reliable, and probably gleaned from data that does not account for factors 1 and 2. Using my own best judgement, averaging the figures and controlling for range I would estimate the fully loaded RADIUS of the Dakota at around 1500 miles in average conditions. Lets try a few approaches taking the UV formula proceeding from an estimated maximum range figure. Lets start with Boeing's Maximum Range figure of 3800 miles. Maximum Range : 3800 miles (126 hexes) Transport Radius : 1900 miles (63 hexes) Extended Radius : 1265 miles (42 hexes) Normal Radius : 950 miles (31 hexes) The actual in-game figures are : Maximum Range : 1470 miles (49 hexes) Transport Radius : NOT GIVEN. However, I know from personal experience in the game that while this is not listed, you can in fact "transport" (troops or supplies) at up to half the Max Range figure, or approximately 24 hexes. Extended Radius : 490 miles (16 hexes) Normal Radius : 367 miles (12 hexes) I believe that what happened was Matrix assumed that the "RANGE" figures given in whatever source they checked for the Dakota was in fact the MAXIMUM RANGE of the aircraft, and their formula thus worked out the normal radius of the aircraft to 367 miles. This would be the simplest explanation for the lack of utility for the Dakotas in the game. Thus, the MEANING of the word RANGE now becomes very important. As I said, most websites do not distinguish between Maximum Range and Normal Range, as the Boeing site does. Lets take some of Bob's numbers and work towards an approach. I personally like Fire in the Sky as a reference. Unfortunately I don't own it. Bob stated that FITS sources recorded a 14 hour flight from CA to Hawaii, and that 500 extra gallons were loaded. This would bring the total fuel load to 1300 gallons. 14 hours cruising time at 185 mph is 2595 miles. This figure is consonant with the UV cruising time and the atlas distance of 2500 miles (adding in some extree miles for head or crosswinds, and possible load). However, we cannot assume this was the MAXIMUM range. Do we know, for example, that they couldn't have loaded more than 500 gallons extra and extended the one way range? Lets take the 800 + 500 fuel figure and try to figure a radius with a normal fuel tank load. 14 hours cruising time on 1300 gallons translates into 8.61 hours cruising time on 800 gallons. This is a mathematical translation, and does not account for added speed/distance due to a reduced load. 8.6 hours cruising time at 185 MPH is 1593 miles. This figure is generally consonant with "range" figures given on all the other websites / databases. Therefore it is reasonable to conclude that the "MAXIMUM RANGE" of the aircraft with full fuel tanks but no additional fuel onboard in jerry cans is 1600 miles, a figure which is also consonant with Boeing's "Normal Range" figure. Therefore, it is rational to conclude further from this data that Boeing's figure of 3800 miles is misleading because this is a theoretical maximum of flight time with additional onboard fuel in jerry cans that can be poured into the fuel tanks during flight. However, the game formula does not appear to account for the relatively standard practice of using onboard jerry can fuel, which could in fact extend the radius of the aircraft by as much as 2200 miles. Of course, the more jerry cans you have on board, the less you can carry as cargo. So, Bob, after this analysis I concede that you are correct that the game ratings are indeed not that far off the mark, and that the word "RANGE" as used in these sites refers to maximum one way range, not radius as I had assumed (and I still maintain the standard parlance is "Range" = radius and "maximum range" = one way range, but there is a lot of confusion among internet sources). However, I think it would be reasonable and accurate to change the Dakota's maximum range figure, based on the data we have. Here's an example of the variance of range data (again, other than the above analysis its impossible to determine whether these people are referring to radius or one way range) : USAF Museum : Range = 1513 miles Australiam Museaum : Range = 1303nm / 1499 miles Aerospace Power Chronicles = 1500 miles "Normal Range" Aerospace Power Chronicles = 2700 miles "Maximum Range" Boeing = 1600 miles "Normal Range" Boeing = 3800 miles "Maximum Range" DC-3 Hangar = 2125 miles A Czech site = 1491 miles I looked at a number of other sites. The most commonly given range figure is 1300 nautical miles or 1500 statute miles. I believe that anything over this figure is taking range data from historical sites describing squadrons or missions in which it was common practice to load jerrycans to extend range. UV lists the cargo capacity of the Dakota at "10000" which is 10,000 pounds or 5 tons. Again we will have huge discrepancy problems if we analyze this. Most sites list 6000 pounds as the load, but some do list the load at between 9 and 10 thousand pounds. So, I believe it was standard practice to load between 1000 and 2000 "pounds" of fuel in the cargo hold in jerrycans. I don't know what that translates into in terms of gallons. One gallon of water weights 8 pounds, aviation fuel weighs 62.5% of water or 5 pounds per gallon. So, 1500 pounds of aviation fuel would be 300 gallons of aviation fuel. According to earlier estimates, the average fuel efficiency of the Dakota is about 2 miles per gallon, so this would add 600 miles to the range. Therefore, I conclude that the Maximum Range of the Dakota in game should be 1500 + 600 or 2100, and the load capacity of the Dakota should be reduced to 8500. This would bring the Dakota ranges into synch with their historical utility as illustrated by, as you pointed out, the ferry flights to Hawaii, and the Hump transport flights of nearly 600 miles to China from Assam, among many other historical examples. With this type of figure, you would get the following : Maximum Range : 2100 miles (70 hexes) Transport Radius : 1050 miles (35 hexes) Extended Radius : 693 miles (23 hexes) Normal Radius : 525 miles (17 hexes) ==== end ====
_____________________________
Last time I checked, the forums were messed up. ;)
|