Cold start wrong position for the hinge pin lock?

[GTFreeFlyer]

Does the hinge pin lock the wings in the up position as well?  Just curious because I thought the pin only engaged something when the wings are spread.  Just found it odd that during a cold start the handle for the hinge pin is in the locked position, which I think is wrong but I’m not 100% sure. 
 

I read the IRL manual and it says that when wings are folded, they are locked by installation of jury struts. I didn’t see anything in the checklist about unlocking the hinge pin before spreading the wings, nor locking the hinge pin after wings are folded. 
 

Just curious how it works, and if the pin’s lock handle really should be in the lock position when you spawn in for cold start, or if this was an oversight?

Thanks!
 

 

[Mike Busutil]

The F4U Corsair’s wings were designed to fold upward for storage on aircraft carriers, a critical feature for naval operations. The wing lock mechanism was intended to secure the wings in both the up (folded) and down (extended) positions to ensure stability during storage or flight.

Up Position (Folded): The wing locks engage to hold the wings securely in the folded position, preventing them from unfolding during carrier operations or transport. This was typically achieved through a combination of hydraulic or manual locking pins and mechanical latches.

Down Position (Extended): The locks also secure the wings in the down position for flight, ensuring they remain rigid under aerodynamic forces. These locks were critical to prevent wing movement during high-stress maneuvers. 

The system was designed to function in both positions, not just the down position, as stability was essential in both configurations. However, the exact mechanism varied slightly depending on the manufacturer (Vought, Goodyear, or Brewster) the Navy mandated manual checks of wing-fold lock pins after a failure, indicating the importance of secure locking in both positions.

Edited June 30 by Mike Busutil

[GTFreeFlyer]

2 hours ago, Mike Busutil said:

The F4U Corsair’s wings were designed to fold upward for storage on aircraft carriers, a critical feature for naval operations. The wing lock mechanism was intended to secure the wings in both the up (folded) and down (extended) positions to ensure stability during storage or flight.

Up Position (Folded): The wing locks engage to hold the wings securely in the folded position, preventing them from unfolding during carrier operations or transport. This was typically achieved through a combination of hydraulic or manual locking pins and mechanical latches.

Down Position (Extended): The locks also secure the wings in the down position for flight, ensuring they remain rigid under aerodynamic forces. These locks were critical to prevent wing movement during high-stress maneuvers. 

The system was designed to function in both positions, not just the down position, as stability was essential in both configurations. However, the exact mechanism varied slightly depending on the manufacturer (Vought, Goodyear, or Brewster) the Navy mandated manual checks of wing-fold lock pins after a failure, indicating the importance of secure locking in both positions.

Good info Mike.  I was looking at page 24 of the operating manual here.  I didn't see any mention of the hinge pin being able to lock the wings when folded.  Just FYI.  I figured there's no contact between the outer and inner wing panels, so the pin wouldn't be able to engage anything? 

[sgray]

While I am sure Mike has done his research and provided a great answer. I found an interesting real world video (https://www.tiktok.com/t/ZP8roShyY/). In this video it sort of shows that the lock is not “on” as he starts the unfold process. Another interesting fact is that while the flap closes, the red visual indicator stay up until the locking mechanism is engaged. Don’t recall the DCS version doing the same with the visual indicator.

I also found that when folded, they used jury struts (red braces) to “lock” the wings folded. These are put on by the ground crew.

Anyway, maybe locking the wing lock mechanism when the wings were folded helped with hydraulic pressure.

It is certainly interesting learning about this iconic bird.

[-Rudel-]

The handle should technically be in the up (pulled) position for cold starts.  I've already mentioned this to our programmers.

[Terry Dactil]

On 7/1/2025 at 3:28 AM, GTFreeFlyer said:

Good info Mike.  I was looking at page 24 of the operating manual here.  I didn't see any mention of the hinge pin being able to lock the wings when folded.  Just FYI.  I figured there's no contact between the outer and inner wing panels, so the pin wouldn't be able to engage anything? 

Another original manual is at https://www.vmfa251.org/pdffiles/Corsair Manual.pdf

Om page 15 is

No mention of the locking pin when folded, only the jury struts.

Maybe there was a later modification, but that seems unlikely. 

(I asked DeepSeek ( AI )  and it found 16 references, none of which was about a lock pin when folded.)

Edited July 3 by Terry Dactil
page number corrected