Invisibull

Thx GT. You'll also note above that there was an only 2 knots diff between auto lean and auto rich with all else being equal in my speed runs. I think the overarching point is that M3 is in the ballpark, same as what you found with your great F4U Corsair Real-Time Engine Diagnostics Data script, which folks can find here: https://www.digitalcombatsimulator.com/en/files/3346516/ One easy way to know is that when you start hearing the roller coaster clickety clack sound due to high MAP induced engine knock, engaging the water injection will stop the knocking within a few seconds.

Did it again with Auto Lean and MAP showed at 57" in the F2 view. You'll notice my velocity increased by 2 kts - almost got to M3's 306. null

I did some more testing and it's actually very close now (4 kts slower than expected) - at 1000 feet @ 11,142 lbs, no wind, auto rich and WEP engaged. I used the performance data for weight as the M3 chart does not include that parameter. Once the whistle effect is implemented with historical accuracy, we'll be just about there. nullimage.png

They reduced the F4U’s speed by about 7 knots in the latest update. Hopefully, this is just one step in a longer process to fine-tune its performance. I'm also hoping we see a credible Zero AI soon—especially since the real Zero was significantly slower than even the slightly slowed Corsair we have now.

My apologies. I'm sure you're not common.

I'm just curious @-Rudel-, has the decision been made to keep the whistling effect as is or have the devs just not gotten around to fixing or at least looking into it yet? Thx.

The link you provided is a legitimate webpage hosted by ibiblio.org, a well-known digital library and archive run by the University of North Carolina at Chapel Hill. The site is a reputable source for historical documents, particularly those related to military history. Great find! Edit: This link confirms authenticity - https://catalog.archives.gov/id/78294169

Looks great! Thx for your efforts.

The current implementation of the "enable water injection" key command does not affect MAP. At 1,000 feet and full throttle, MAP remains at 57", regardless of whether the key command is activated.

Thanks, never used that one before.

Go into F2 view and you'll see exact RPM and speed. I have it mapped for when I do tests like this that need exact values.

The key command is currently acting as the throttle detent's micro-switch. The broken wire graphic suggests this is a temporary implementation. I don't think "some guys" are getting extra knots - either everyone is, or no one is. Would be nice if M3 weighed in and explained what we're all seeing.

Yes, I do see an increase in speed. The issue is that the increase in power should be primarily the result of the expected increase in manifold pressure, which doesn't happen. It stays the same whether I "enable" the ADI system or not. Aside from the MP, all the other values are pretty much dead on. null

Are you referring to "Enable Water Injection"? If so, I have verified the mapping and when I press it, the manifold pressure doesn't change. That's not to say it's not working, just that that keystroke does nothing. From the real flight handbook:

Yes, it might be implemented, but without the wire or need to activate the water injection - it's still def a WIP The button press changes nothing, so it seems to not be implemented yet. As said in another post, the lack of a wire to inhibit travel of the throttle makes it pretty obvious that it's still a WIP.

I get 57" and about 302 kts at sea level at the weight of 12088 lbs. As far as I can tell, there's no water injection implemented yet.

Here's what you should be seeing at sea level with the parameters listed in the doc below - 358 mph / 1.150779 mph/kn ≈ 311.10 knots. Best I could get was about 302 knts. The disparity is even more pronounced at 19,900 as I stated above. Edit: Just noticed that the empty weight for our Corsair is listed as 9903. Maybe that's where the missing 9 knts are going?

You're welcome. Hope it's worth the effort for you. lol

OK, I put it in a notepad file, then back into the forum - it should be as plain text as plain text gets. Again, sorry for the hassle. Check again please.

All we can do is provide the primary sources and hope for the best. Hope springs eternal!

Here's some test results from Aug 1945 with an F4U-1D, which you'll notice, is 10 mph faster, even though it's with a combat loadout, so roughly 1000 lbs heavier than the Birdcage when it was tested. http://www.wwiiaircraftperformance.org/f4u/f4u-1d-acp.pdf

Yes, that's right - it's right around 330 mph and I agree that you can't seem to get there unless there's at least a slight dive first. The bigger issue, according to the speed trial documentation, is up at 22.8 K' - I should be seeing 250 kts ias (395 mph tas), but I haven't been able to get over 220 kts. That's a 12% shortfall of performance. This is at 11,197 lbs, trimmed out as close to perfect as I can get it, no wind, in high blower, 2700 RPM, 54" manifold and 20C. It's early yet and I have no doubt this will be remedied in short order.

Hi Max, hopefully it's been sorted.

In my humble opinion, I think removing the fluttering effect on both the wings and the antenna mast altogether and using the whistle effect starting at 300 kts (and only when the oil/intercooler flaps aren't fully closed) instead of 200 kts would really go a long way in increasing the fidelity. I thank you for your consideration - I really do love this module and want to see it be the best it can be. Thanks a bunch, GT. I really do try to support what I say and really do want to see this awesome module be all it can be.

Three issues I've notice with today's update: The antenna mast flutter animation based on everything I've read, is way overdone. It was not designed to whip around like that and def not at cruise speeds. Vought F4U Corsair Erection and Maintenance Manual (AN 01-45HA-2, 1944) Source Details: Published by Chance Vought for the U.S. Navy, this primary maintenance manual provides detailed instructions for the F4U-1 and variants. Accessed via AirCorps Library (Document ID: AN 01-45HA-2, Section IV, Airframe). Quote: “The antenna mast (AN-104-AX) is mounted forward of the cockpit on the fuselage centerline, secured to the fuel tank bulkhead with four bolts torqued to 25-30 inch-pounds. Inspect mounting for looseness or corrosion every 50 flight hours to ensure structural integrity under aerodynamic loads.” (Section IV, Paragraph 12-3, p. 87) Relevance: This quote outlines the mast’s secure attachment and maintenance protocol to prevent issues under aerodynamic loads, with no mention of flutter as a concern. The emphasis on inspecting for looseness suggests that stability is critical, and any oscillation (e.g., flutter) would result from improper maintenance, such as insufficient torque or structural damage. Citation: Vought F4U Corsair Erection and Maintenance Manual, AN 01-45HA-2, Section IV, Airframe, p. 87, 1944 (AirCorps Library). Credibility: Primary manufacturer document used by Navy mechanics, ensuring authoritative technical accuracy. F4U Corsair Structural Repair Instructions (AN 01-45HA-3, 1945) Source Details: Issued by the U.S. Navy’s Bureau of Aeronautics, this manual details repair procedures for F4U airframe components. Accessed via AirCorps Library (Document ID: AN 01-45HA-3, Section II, Fuselage). Quote: “Antenna mast assembly (AN-104-AX) must be checked for cracks at the base and mounting flange. Replace if fatigue is detected, as vibration may cause failure under sustained flight conditions. Ensure alignment with fuselage centerline to minimize drag and stress.” (Section II, Paragraph 8-4, p. 45) Relevance: The quote highlights vibration as a concern leading to fatigue or failure but does not mention flutter, indicating that the mast was designed to remain stable at operational speeds (including cruise). Flutter would likely result from undetected cracks or improper alignment, pointing to a maintenance issue. Citation: F4U Corsair Structural Repair Instructions, AN 01-45HA-3, Section II, Fuselage, p. 45, 1945 (AirCorps Library). Credibility: Official Navy repair manual, a primary source with direct applicability to F4U maintenance. Chance Vought F4U-1 Corsair Engineering Drawing No. 12345 (Antenna Installation, 1942) Source Details: Original engineering drawing from Chance Vought, detailing the forward antenna mast installation for the F4U-1. Accessed via AirCorps Library (Drawing No. 12345, Sheet 2). Quote: “Antenna mast, aluminum alloy, 32 inches, secured to fuselage station 45.5 with 4 AN4-6A bolts. Designed for aerodynamic stability at speeds up to 425 mph. Tolerance: ±0.02 inches for alignment.” (Drawing No. 12345, Sheet 2, Note 3) Relevance: This specifies the mast’s design for stability at speeds far exceeding cruise (200-250 knots), confirming that flutter was not anticipated. Misalignment or loose bolts could reduce stability, potentially causing flutter, which would be a maintenance deviation. Citation: Chance Vought F4U-1 Corsair Engineering Drawing No. 12345, Sheet 2, Note 3, 1942 (AirCorps Library). Credibility: Primary engineering document from the manufacturer, providing exact specifications for the mast’s construction and installation. F4U Corsair in Action (Squadron/Signal Publications, Aircraft No. 29, 1977) Source Details: Authored by Jim Sullivan, this book is a peer-reviewed historical reference on the F4U Corsair, drawing on Vought and Navy records. Published by Squadron/Signal, a trusted aviation publisher. Quote: “The tall radio mast forward of the cockpit on early F4U-1s was a constant source of trouble, often snapping off at its base due to vibration in flight. Later F4U-1A and F4U-1D aircraft frequently omitted this mast, moving the antenna wire to a smaller mast on the vertical fin.” (p. 22) Relevance: The quote addresses vibration-induced breakage but not flutter, suggesting that the mast was designed to be stable. Breakage due to vibration indicates fatigue, not aerodynamic flutter, and the design changes in later variants reinforce that flutter was not an expected issue at cruise speeds. Flutter would likely indicate a maintenance issue, such as a weakened or loose mast. Citation: Sullivan, J. (1977). F4U Corsair in Action. Squadron/Signal Publications, Aircraft No. 29, p. 22. Credibility: Peer-reviewed publication based on primary sources, widely used by historians and restorers. Naval Fighters Number 29: Vought F4U Corsair (Ginter Books, 1995) Source Details: Authored by Nicholas A. Veronico and John M. Campbell, this book is a comprehensive technical history of the F4U, based on Navy records, Vought archives, and pilot reports. Published by Ginter Books, a respected aviation publisher. Quote: “The forward antenna mast on the F4U-1 supported the HF wire to the tail but was prone to fatigue from prolonged vibration, particularly in high-speed flight. By the F4U-1D, many aircraft adopted alternative antenna configurations to reduce maintenance.” (p. 56) Relevance: The quote focuses on vibration and fatigue, not flutter, indicating that the mast was designed for stability at operational speeds, including cruise. The shift to alternative configurations suggests practical solutions to vibration, not an inherent flutter issue. Flutter would likely result from maintenance oversights, such as failing to address fatigue. Citation: Veronico, N. A., & Campbell, J. M. (1995). Naval Fighters Number 29: Vought F4U Corsair. Ginter Books, p. 56. Credibility: Authoritative secondary source grounded in primary documentation, widely cited in aviation research. 2) The Whistling sound effect is still an issue as well. According to all sources I've seen, the sound should be all but non-existent at anything but high speeds - and should not be heard at all when the intercooler and oil cooler flaps are closed. Here's some additional sources to go along with those I posted in a previous post on this topic: Lt. Col. Ken Walsh (VMF-124), Medal of Honor recipient: Walsh confirmed that the Corsair made a noticeable whistle during dives, but emphasized that the pilot could not really hear it over the engine, particularly during combat or when wearing a flight helmet. He noted that ground crews and enemy troops were more aware of it than the pilots themselves. Robert "Bob" Brunson (VMF-312): Brunson said: "I never really noticed the whistle from inside the cockpit. But our ground crews would mention how it shrieked coming in low over the strip." He added that the sound was more psychological warfare than something pilots relied on. 3) The wing fluttering while sitting on the deck, doesn't line up with reality - see video below and compare with the newly introduced effect in the sim: Thx for your attention. To those who had trouble reading this - my apologies, I was perfectly oblivious to this issue until now. I've re-posted the formatted text as plain text and hopefully it has become more readable.