Grumman F8F-1B

[ElBarca 1,160]

Technical description:
 
Engine Name: twin-row, 18-cylinder, air-cooled radial engine Pratt & Whitney R-2800-34W
Dry Weight: 2500 Pounds
Fuel: 150 Octane
 
Power Settings:
Normal Power:
Low Blower Supercharger: 2,600 RPM 41 InHG 1,700 HP at 8,500 ft
High Blower Supercharger: 2,600 RPM 42 InHG 1,500 HP at 18,500 feet. 
 
Combat Power, WEP: 5 Minute Limit
Low Blower; 2,800 RPM 60" HG, 2,350 HP at Sea level
High blower: 2,800 RPM 70" HG 2,400 HP at 7,000 ft
                    2,800 RPM 49.5” HG 1,700 HP at 17,000 ft

 
Propeller Data: 4-blade AeroProducts # H-20c-156-5M5
Diameter: 12'7"
 
Basic Geometric Data:
Length: 27' 6”
Wingspan: 35' 6”
Height: 13' 8” while on the ground, wheels to highest point.
Wing Area (including Ailerons): 244 sq ft.
 
Weight:
Empty Weight: 7,070 pounds
Weight Oil: 14 Gallons, 105 pounds.
Weight Fuel: 185 Gallons, 1,110 pounds.
Gun Weight:  4x20mm Cannons - 876 pounds.
Ammo Weight: 820-20mm rounds - 492 pounds.
Take Off Weight, full internal fuel and ammo: 10,364 pounds
 
Stall Speed at max fuel and ammo weight with no power: 86 knots - 99 mph
Stall Speed at max fuel and ammo weight with flaps down and no power: 82 knots - 93 mph
 
Level speed performance (9970 lbs):

 

WEP Power
Altitude (Feet)  -  Supercharger Stage   True Speed (MPH)
00,000                             Low                            406
15,000                             High                           445

 

100% Throttle
Altitude (Feet)  -  Supercharger Stage  - True Speed (MPH)
00,000                         Low                                350 
22,000                         High                               415 
 
Time to Climb (9215 lbs):  In minutes
Altitude ( Feet)    WEP     100%
10,000                 2.13       3.0
20,000                  4.8        6.7

[tenkte 6,523]

Metric MUSTARD race!

 

Nevertheless good job!!  :good:

 

Can we get charts too?

Edited July 1, 2014 by tenkte

[PapaShteve 1,687]

How is take off weight 10,364 pounds ? That's heavier then a F8F-2 at combat weight. According to what you listed here - 

 

Weight:
Empty Weight: 7,070 pounds
Weight Oil: 14 Gallons, 105 pounds.
Weight Fuel: 185 Gallons, 1,110 pounds.
Gun Weight:  4x20mm Cannons - 876 pounds.
Ammo Weight: 820-20mm rounds - 492 pounds.
Take Off Weight, full internal fuel and ammo: 10,364 pounds
 

The total weight comes to 9653 pounds. Where is the other 711 pounds coming from?

[DaReaILegend 947]

. Where is the other 711 pounds coming from?

american pilots  :Ds

[PapaShteve 1,687]

american pilots :Ds

Funny (somewhat), but seriously 711 pounds of mystery weight is really strange.

[PapaShteve 1,687]

No reply? If the 10 364 pound take off weight is not a typo, then something is really wrong.

 

From the F8F manual:

 

F8F-1B weight is listed at 10 000 pounds fully loaded, including 3 bomb racks and 2 rocket launchers on board.

 

Both of the books I have in my possestion on the F8F Bearcat ( "Grumman F8F Bearcat: Super Profile" and "Naval Fighters Number Eighty: Grumman F8F Bearcat") list the F8F-1B combat loaded weight at 9672 pounds. This is the clean weight with no bomb racks or rocket launchers.

 

Weight:

Empty Weight: 7,070 pounds
Weight Oil: 14 Gallons, 105 pounds.
Weight Fuel: 185 Gallons, 1,110 pounds.
Gun Weight:  4x20mm Cannons - 876 pounds.
Ammo Weight: 820-20mm rounds - 492 pounds.
Take Off Weight, full internal fuel and ammo: 10,364 pounds

Again doing the math here, the wieght you listed, comes to 9653 pounds. This wieght is nearly the as the one listed in my sources.

 

10 364 pounds is simply an incorrect wieght for a fully loaded clean F8F-1B.

Edited July 3, 2014 by PapaShteve

[Ottobon 19,138]

I have to side with Steve, where is the extra 711lbs coming from?

[MisterGrinder 198]

Flip at landing does not indicate 10000lbs.

Must have revolutionary disc brakes

Always on it´s back like a wh re

[WildBlueYonder 3,072]

The performance of this aircraft is strange, since it's doing F8F-2 performance but with a weight that's not representative of neither aircraft. 

[PapaShteve 1,687]

The performance of this aircraft is strange, since it's doing F8F-2 performance but with a weight that's not representative of neither aircraft.

It's very odd. This may explain the very sluggish rolling of the f8f-1b compared with the f8f-1 as well.

[ElBarca 1,160]

No reply? If the 10 364 pound take off weight is not a typo, then something is really wrong.

 

From the F8F manual:

 

F8F-1B weight is listed at 10 000 pounds fully loaded, including 3 bomb racks and 2 rocket launchers on board.

 

Both of the books I have in my possestion on the F8F Bearcat ( "Grumman F8F Bearcat: Super Profile" and "Naval Fighters Number Eighty: Grumman F8F Bearcat") list the F8F-1B combat loaded weight at 9672 pounds. This is the clean weight with no bomb racks or rocket launchers.

 

Again doing the math here, the wieght you listed, comes to 9653 pounds. This wieght is nearly the as the one listed in my sources.

 

10 364 pounds is simply an incorrect wieght for a fully loaded clean F8F-1B.

 

Thank you. We will look into this. However that should not affect performance. Since we had designed and tested it for the specific weight 9970 lbs

[Danneskjold 3,092]

The number comes from the guns and ammo weight differences.  It'll be clearer when the F8F-1 data is released.

 

 

F8F-1 empty weight of 7,070 pounds.  Full internal weight of 9,386 pounds.  .50 guns weight: 244 pounds.  .50 cal ammo weight: 360 pounds.

 

F8F-1B gun weight, 4-20mm's: 876 pounds.  Ammo weight: 492 pounds.

 

Guns and ammo weight difference: 764 pounds.  9,600 + 764 = 10,364 pounds

 

 

 

Please check my numbers, they could be off, or wrong, or I could have made incorrect assumptions.

[PapaShteve 1,687]

The number comes from the guns and ammo weight differences.  It'll be clearer when the F8F-1 data is released.

 

 

F8F-1 empty weight of 7,070 pounds.  Full internal weight of 9,386 pounds.  .50 guns weight: 244 pounds.  .50 cal ammo weight: 360 pounds.

 

F8F-1B gun weight, 4-20mm's: 876 pounds.  Ammo weight: 492 pounds.

 

Guns and ammo weight difference: 764 pounds.  9,600 + 764 = 10,364 pounds

 

 

 

Please check my numbers, they could be off, or wrong, or I could have made incorrect assumptions.

That is incorrect. The USN SAC lists the F8F-1, fully loaded with full fuel, guns and ammo and 1 fuselage bomb rack, as 9334 pounds.

 

[spoiler][/spoiler] 

 

Column 4. - look at the second page, bottom. 

 

"One MK51-9 fuselage bomb rack and sway-bracing. Wing bomb racks and rocket launchers not aboard."

 

Extrapolating the figures from the SAC we can estimate the weight of the 3 MK-51 bomb racks and the 2 sets (4) MK9-1 rocket launchers.

 

Column 1. includes 2 wing mounted bomb racks and 1 fuselage bomb rack = 3 total. No rocket launchers. 

 

Weight - 9386 pounds.

 

Column 4. 1 fuselage bomb rack. No rocket launchers.

 

Weight - 9334 pounds.

 

 

Now assuming the wing racks and fuselage share the same weight that would equal 26 pounds per each MK-51 Bomb rack. (9386 - 9334 = 52, the weight of 2 racks. 52/2 = 26 pounds weight of each rack). 

 

A totally clean, full fuel, guns and ammo, F8F-1 would be estimated around 9308 pounds. (9334 - 26 = 9308).

                                                                                                                   

 

We know the F8F-1 fully equipped, with bomb racks and 2 sets (4) rocket launchers, is 9600 pounds. This is the number in the manual. See below:

 

 

 

 

If we take the F8F-1 wieght of 9386 (3 bomb racks) and subtract this from the weight above we get 214 pounds, the wieght of 4 Mk9-1 rocket launcher.

 

214/4 = 53.5 pounds per MK9-1 rocket launcher wing rack. So:

 

F8F-1 Clean, fully loaded -

 

9308 pounds

 

+ 3 MK51 bomb racks, 78 pounds (26x3=78)

+ 4 MK9-1 Rocket Launchers, 214 pounds (53.5 x 4=214)

= 9600 total.

                                                                                                 

 

If we do the same with the F8F-1B now, using the number ElBarca says that they modelled the F8F-1B with, (9970 pounds) we can figure out the weight of a clean F8F-1B:

 

F8F-1B:  9970 Pounds

 

- 3 MK51 bomb racks, 78 pounds (26x3=78)

- 4 MK9-1 Rocket Launchers, 214 pounds (53.5 x 4=214)

= 9678 total.

 

Look at that, only 6 pounds off of my sources for the F8F-1B weight ("Grumman F8F Bearcat: Super Profile" and "Naval Fighters Number Eighty: Grumman F8F Bearcat") say the F8F-1B weighs 9672 pounds fully loaded, clean.

                                                                                                                                                          

 

It appears you added the weight of the F8F-1B on top of the F8F-1's weight, including the F8F-1s 4x50 cal and ammunition weight? 

 

From the OP - 

 

Weight:

Empty Weight: 7,070 pounds
Weight Oil: 14 Gallons, 105 pounds.
Weight Fuel: 185 Gallons, 1,110 pounds.
Gun Weight:  4x20mm Cannons - 876 pounds.
Ammo Weight: 820-20mm rounds - 492 pounds.

 

This equals to 9653 pounds for the F8F-1B. Which is nearly the same as the clean weight listed in my books and the estimate here. So the take off weight of 9970 pounds is including bomb racks and  rocket launchers. Why are we modelling the pylons in if we are flying the aircraft in game in a clean condition?

Edited July 5, 2014 by PapaShteve

[Danneskjold 3,092]

You missed the point.  If the only thing that was different was the guns and ammo, then we can calculate the weight difference based off of the weights of the guns alone.

[PapaShteve 1,687]

You missed the point.  If the only thing that was different was the guns and ammo, then we can calculate the weight difference based off of the weights of the guns alone.

Well I have never seen a combat loaded weight of a F8F-1B that heavy at 10 364 pounds, and that is 364 pounds heavier then the weight listed in the manual and that is fully loaded, even listed with racks and launchers. Only thing that comes close to that weight is the F8F-2. Something is wrong.

Edited July 6, 2014 by PapaShteve

[SunsetShimmers 7,929]

This http://www.wwiiaircraftperformance.org/F8F/F8F-1_Standard_Aircraft_Characteristics.pdf got uploaded to http://www.wwiiaircraftperformance.org/ at some point without notification; I only noticed it when I went looking for performance data on the Bearcat today to answer a query someone had.

 

Data is for F8F-1; the 1B differs in this:

 

- It is 442 lbs heavier

- High speed is 2 knots less

- Rate of climb at sea level is 250-300 ft/min less

 

 

Engine power ratings:

 

Combat (I think this is WEP with water injection): 2,800 RPM, 2,750 BHP at sea level, 2,450 BHP at 9,600 feet

Military (I think this is WEP without water injection): 2,800 RPM, 2,100 BHP at 3,000 feet, 1,700 BHP at 16,000 feet

Normal (I think this is just 100% power): 2,600 RPM, 1,700 BHP at 8,500 feet, 1,500 BHP at 18,500 feet

 

 

Performance data for each power rating, which is at combat weight (no external stores, full internal tank).

 

Combat:

Top speed at Sea Level = 366 knots / 678 kph

Max Speed = 372 knots / 689 kph at 18,800 feet / 5,730 meters

Rate of climb at Sea Level = 5,610 ft/min / 28.50 m/s

Time to Climb 20,000 feet = 4.9 minutes

 

 

Military:

Top speed at Sea Level = 331 knots / 613 kph

Max Speed = 372 knots / 689 kph at 18,800 feet / 5,730

Rate of climb at Sea Level = 4,830 ft/min / 24.54 m/s

Time to Climb 20,000 feet = 5.2 minutes

 

 

Normal:

Top speed at Sea Level = 307 knots / 569 kph

Max Speed = 360 knots / 667 kph  at 20,000 feet / 6096 meters

Rate of climb at Sea Level = 3,750 ft/min / 19.05 m/s

Time to Climb 20,000 feet = 6.2 minutes

 

 

 

With the previous adjustments for the F8F-1B done:

 

Combat:

Top speed at Sea Level = 364 knots / 674 kph

Max Speed = 370 knots / 685 kph at 18,800 feet / 5,730 meters

Rate of climb at Sea Level = 5,310 ft/min / 26.97 m/s

 

 

Military:

Top speed at Sea Level = 329 knots / 609 kph

Max Speed = 370 knots / 685 kph at 18,800 feet / 5,730

Rate of climb at Sea Level = 4,530 ft/min / 23.01 m/s

 

 

Normal:

Top speed at Sea Level = 305 knots / 565 kph

Max Speed = 358 knots / 663 kph  at 20,000 feet / 6096 meters

Rate of climb at Sea Level = 3,450 ft/min / 17.53 m/s

 

 

This performance is quite a bit difference from the data posted in the OP.

 

 

The OP lists the following speeds for WEP:

Sea Level = 653 kph

At 15,000 feet = 716 kph

 

 

And for 100%:

Sea Level = 563 kph

At 15,000 feet = 668 kph

 

 

That puts the speeds with WEP as lower than the Standard Aircraft Characteristics Sea Level, higher max speed at altitude. Speeds for 100% power rating appears to be correct, although the top speed at altitude is achieved 5,000 feet lower.

 

Climb times to 20,000 feet is close (4.9 to 4.8 minutes) for WEP, but significantly different for 100% (6.7 to 6.2 minutes), although this may be due to the F8F-1B's climb being worse than the F8F-1.

 

Engine BHP ratings are also different in the OP, with max of 2350 HP at Sea Level, versus 2750 in the Standard Aircraft Characteristics.

 

 

EDIT: 

 

I just did a test of the F8F-1 in RB settings with a full fuel tank (albeit with mouse aim and auto engine management), and could only hit 551 kph without WEP, and 611 kph with WEP at Sea Level.

 

This indicates the F8F-1 is underperforming at Sea Level speeds by 12-14 kph without WEP and 42-63 kph with WEP (depending on source).

 

 

EDIT 2:

 

Just tested F8F-1 again, same as above, this time at 15,000 feet altitude. Without WEP, it could reach 613 kph, and with WEP it could reach 629 kph.

This is much lower than the 716 kph with WEP at 15k feet in the datasheet in the OP, and also less than the 663 / 676 kph (without/with WEP) at that altitude in the Standard Aircraft Characteristics file.

Edited July 25, 2014 by Cuteling

[PapaShteve 1,687]

This http://www.wwiiaircraftperformance.org/F8F/F8F-1_Standard_Aircraft_Characteristics.pdf got uploaded to http://www.wwiiaircraftperformance.org/ at some point without notification; I only noticed it when I went looking for performance data on the Bearcat today to answer a query someone had.

Data is for F8F-1; the 1B differs in this:

- It is 442 lbs heavier
- High speed is 2 knots less
- Rate of climb at sea level is 250-300 ft/min less


Engine power ratings:

Combat (I think this is WEP with water injection): 2,800 RPM, 2,750 BHP at sea level, 2,450 BHP at 9,600 feet
Military (I think this is WEP without water injection): 2,800 RPM, 2,100 BHP at 3,000 feet, 1,700 BHP at 16,000 feet
Normal (I think this is just 100% power): 2,600 RPM, 1,700 BHP at 8,500 feet, 1,500 BHP at 18,500 feet


Performance data for each power rating, which is at combat weight (no external stores, full internal tank).

Combat:
Top speed at Sea Level = 366 knots / 678 kph
Max Speed = 372 knots / 689 kph at 18,800 feet / 5,730 meters
Rate of climb at Sea Level = 5,610 ft/min / 28.50 m/s
Time to Climb 20,000 feet = 4.9 minutes


Military:
Top speed at Sea Level = 331 knots / 613 kph
Max Speed = 372 knots / 689 kph at 18,800 feet / 5,730
Rate of climb at Sea Level = 4,830 ft/min / 24.54 m/s
Time to Climb 20,000 feet = 5.2 minutes


Normal:
Top speed at Sea Level = 307 knots / 569 kph
Max Speed = 360 knots / 667 kph at 20,000 feet / 6096 meters
Rate of climb at Sea Level = 3,750 ft/min / 19.05 m/s
Time to Climb 20,000 feet = 6.2 minutes



With the previous adjustments for the F8F-1B done:

Combat:
Top speed at Sea Level = 364 knots / 674 kph
Max Speed = 370 knots / 685 kph at 18,800 feet / 5,730 meters
Rate of climb at Sea Level = 5,310 ft/min / 26.97 m/s


Military:
Top speed at Sea Level = 329 knots / 609 kph
Max Speed = 370 knots / 685 kph at 18,800 feet / 5,730
Rate of climb at Sea Level = 4,530 ft/min / 23.01 m/s


Normal:
Top speed at Sea Level = 305 knots / 565 kph
Max Speed = 358 knots / 663 kph at 20,000 feet / 6096 meters
Rate of climb at Sea Level = 3,450 ft/min / 17.53 m/s


This performance is quite a bit difference from the data posted in the OP.


The OP lists the following speeds for WEP:
Sea Level = 653 kph
At 15,000 feet = 716 kph


And for 100%:

Sea Level = 563 kph
At 15,000 feet = 668 kph


That puts the speeds with WEP as lower than the Standard Aircraft Characteristics Sea Level, higher max speed at altitude. Speeds for 100% power rating appears to be correct, although the top speed at altitude is achieved 5,000 feet lower.

Climb times to 20,000 feet is close (4.9 to 4.8 minutes) for WEP, but significantly different for 100% (6.7 to 6.2 minutes), although this may be due to the F8F-1B's climb being worse than the F8F-1.

Engine BHP ratings are also different in the OP, with max of 2350 HP at Sea Level, versus 2750 in the Standard Aircraft Characteristics.


EDIT:

I just did a test of the F8F-1 in RB settings with a full fuel tank (albeit with mouse aim and auto engine management), and could only hit 551 kph without WEP, and 611 kph with WEP at Sea Level.

This indicates the F8F-1 is underperforming at Sea Level speeds by 12-14 kph without WEP and 42-63 kph with WEP (depending on source).


EDIT 2:

Just tested F8F-1 again, same as above, this time at 15,000 feet altitude. Without WEP, it could reach 613 kph, and with WEP it could reach 629 kph.
This is much lower than the 716 kph with WEP at 15k feet in the datasheet in the OP, and also less than the 663 / 676 kph (without/with WEP) at that altitude in the Standard Aircraft Characteristics file.

That is the document I recently obtained from the national naval aviation museum, mike Williams updated his site to include it after I posted it on the ww2 aircraft forums. It was never made public on the internet until I posted it. This performance is not in game as it was previously never seen online, until last week when I put it up.

The F8F-1 and F8F-1b in game have different FMs. F8F-1 is modelled with 100/130 octane based on the June 1945 SAC. F8F-1b is modelled after the manuals 115/145 octane.

[SunsetShimmers 7,929]

That is the document I recently obtained from the national naval aviation museum, mike Williams updated his site to include it after I posted it on the ww2 aircraft forums. It was never made public on the internet until I posted it. This performance is not in game as it was previously never seen online, until last week when I put it up.

The F8F-1 and F8F-1b in game have different FMs. F8F-1 is modelled with 100/130 octane based on the June 1945 SAC. F8F-1b is modelled after the manuals 115/145 octane.

 

Ooooh, nice work!

 

And thanks for explaining the differences in the -1 and -1b modelling.

[PapaShteve 1,687]

Some things are not adding up about this data sheet.

1. Are you certain that the F8F-1 manuals climb data chart is using water injection/combat power?
at the bottom it says "Power Plant Settings:(details on fig. (this is blank) Section III.)

Section III details the different power settings but the chart above does not reference which figure (setting) the data was obtained using. Judging by the lighter then combat weight used - 9215 pounds instead of 9672 pounds combat weight - the chart it looks to be a military power climb at 115/145 octane. Using 115/145 fuel military power runs at 58" HG which produces 2300 BHP at SL. This increase in power and 457 pounds of less weight looks to show that this is a military power climb and not a combat power (WEP) climb.


2. and this is very odd, in the OP you list time to climb at 100% (I assume military power?) as 3.0 minutes to 10k feet and 6.7 minutes to 20K feet. That seems to be taken from the June 1945 SAC (100/130 octane) at normal power climb, not military power.

Time to Climb (9215 lbs): In minutes
Altitude ( Feet) WEP 100%
10,000 2.13 3.0
20,000 4.8 6.7

***Edit (October 2014): There is no way to use military power on the F8F in game. 100% throttle in game has the F8F running at normal power. The F8F's don't have military power settings modelled in game, why? The F6F Hellcat and F4U Corsair can run at Military power, why cant the F8F? Edited October 29, 2014 by PapaShteve

[PapaShteve 1,687]

Combat Power, WEP: 5 Minute Limit
 

Also where does this information come from? If you take this from the manual from the image below, then this is incorrect. These are engine temperature operation limits. Military power shows a 5 minute limit at 260 degrees as well:

 

 

F8F-1/1B official SAC shows a recommended 10 minute usage of WEP (combat power). 

 

[PapaShteve 1,687]

There is no way to use military power on the F8F in game. 100% throttle in game has the F8F running at normal power. The F8F's don't have military power settings modelled in game (or if they do, we can't use it), why? The F6F Hellcat and F4U Corsair can run at Military power, why cant the F8F?? Makes no sense.

[The_Pro_At_War 3,683]

Whats "Military" Power?

[Rumpullpus 3,883]

Whats "Military" Power?

its what the US called full throttle. usually without ADI.

 

there's "Continuous" power (highest power the engine can withstand without overheating at some point)

 

"normal" power (factory/normal everyday use)

 

"military" power (combat use)

 

and "War Emergency" power (obviously for emergencies)

Edited October 29, 2014 by Rumpullpus

[The_Pro_At_War 3,683]

Is it just me or Rolls the F8F-1B Worse than the F8F-1B?

And it feels so that the F8F-1 Also turn better.

[MessereMesser 910]

http://www.wwiiaircraftperformance.org/F8F/F8F-1_Standard_Aircraft_Characteristics.pdf this datasheet says SL level speed of 366kn, that's about 677kph

Also I don't know if it's relevant to the F8F1B, but the normal F8F1 with 50cals, should carry 1200 rounds according to this, not 1050 rounds.