Skyraider cooling flaps/shutters

[RidgeRunner]

A question for the collective brains that are attuned to the ins and outs of the skyraider. Q: were the cooling shutters and cowl flaps tied so that they worked in sync? My intention is to build my current Skyraider with shutters open but does that mean I need to show the cowl flaps open too?

 

thanks in advance.

 

 

Edited April 5, 2020 by RidgeRunner

[Work In Progress]

They are not mechanically interconnected but are sequenced off a common switch.

Rather than write a long essay, may I refer you to post #3 in this thread which has chapter and verse?

https://www.tapatalk.com/groups/hyperscale/skyraider-cowl-flaps-question-t141869.html

 

For an aircraft parked and closed up, good airmanship dictates both closed. For something depicted as if the pilot has just climbed out, then rear flaps closed / nose shutters open is a possibility, so feel free to have it if it's the configuration that appeals to you. For something with a pilot sitting in the cockpit, but on the ground, then everything open.

Edited April 5, 2020 by Work In Progress

[RidgeRunner]

Thanks again @Work In Progress and @72modeler. I've now realised that every image I have of "MP" shows the shutters and cowl flaps closed while on the ground and power off. Even so, the information is very useful and will help later on with other Skyraider builds.

 

Martin

[72modeler]

@Tailspin Turtle

 

Tommy, I have a real dilemma here regarding the front cowling shutters on an AD. Why were they adjustable? I don't see how they  increased cooling over a normal open front cowling ring. I could see them being used to stop salt spray or salt air ingestion when parked, or like many Soviet aircraft to speed warm-up in frigid conditions, but what purpose would they serve being partially open? From examining my Ginter monographs, the Skyraider Modelers Guide, your AD blogs, and my two In Actions, there is no real description/diagram/photo of the shutters. or their function. It looks like they were fitted beginning sometime during AD-4 production, mainly the multi-seat variants? I have a friend who flew USAF A-1E's and A-1H's in SEA, and he told me they disabled/removed them from their Spads.

 

@RidgeRunner's AD-4N build is what really piqued my probably insane interest in this topic, but I am dying to know why they were installed and how they worked-  can you shed some light on the subject? Since in most photos, the cowl flaps appear to be open or partially open after shutdown, you can't see the rod that indicated the front shutters and the cowl flaps were fully closed, which would confirm that the Spad in a photo had them fitted. Help me, Obie Wan!

Mike 

 

"I'll take Skyraider modeling trivia for five hundred, Alex!"

[Tailspin Turtle]

Dive bombing at a steep angle even with the dive brakes extended risked shock cooling of the engine cylinder heads, which was hard on the engine and risked failure following the pullout when full power was reapplied. Presumably closing them all the way (good for quicker warmup as you noted: aircraft piston engines need to be warmed up before full power is applied) might be too much in dives at some atmospheric conditions so the pilot would monitor the cylinder head temperature and partially open them if needed. Saying more or even what I've written so far means to start making things up. I vaguely remember that the rod didn't retract completely and was fully extended when the nose flaps had fully closed off the cowl opening. Also see the picture and description here: http://tailspintopics.blogspot.com/2011/10/ad-skyraider-modeling-notes.html

Edited April 6, 2020 by Tailspin Turtle

[72modeler]

Thanks, Tommy! Your description makes sense and might well be the reason that the USAF removed or disabled the front shutters  on their Spads, as they were not used for dive bombing and were flown almost exclusively at low level. You have made @RidgeRunner's day with your post! I appreciate your taking the time to reply.

Mike

 

So, when are we going to get a big fat two-volume monograph on the F4U/AU-1? Pretty please?

[Finn]

Here is another view of the cowl pin from a different angle:

 

http://images.google.com/hosted/life/e046aec278bf207a.html

 

Click on the thumbnails under Related images for a few more A-1 pics.

 

Jari

[Wez]

This is good gen! 

 

Good and sound engineering explanation Tommy.

 

Keep up the good work.

 

Thanks

 

Wez

[e8n2]

4 hours ago, 72modeler said:

Thanks, Tommy! Your description makes sense and might well be the reason that the USAF removed or disabled the front shutters  on their Spads, as they were not used for dive bombing and were flown almost exclusively at low level. You have made @RidgeRunner's day with your post! I appreciate your taking the time to reply.

Mike

 

So, when are we going to get a big fat two-volume monograph on the F4U/AU-1? Pretty please?

Hahahahahahahaha!  Good one Mike!  For the record, I would also plunk down my money for a two volume set on the Corsair as well. 

Later,

Dave

[Learstang]

So if I'm doing a USAF Special Ops Skyraider (which I am), I should just leave the cooling shutters off?

 

Regards,

 

Jason

[RidgeRunner]

Thanks a million, Mike @72modelerand Tommy @Tailspin Turtle.

 

Jason @Learstang, my understanding - happy to be corrected - is that on those machines they were simply deactivated and wired open.

 

Back to my subject machine "TR-KMP", she had the shutters and they were operational :).

 

Martin

Edited April 7, 2020 by RidgeRunner

[Wez]

22 minutes ago, RidgeRunner said:

Thanks a million, Mike @72modelerand Tommy @Tailspin Turtle.

 

Jason @Learstang, my understanding - happy to be corrected - is that on those machines they were simply deactivated and wired open.

 

Back to my subject machine "TR-KMP", she had the shutters and they were operational :).

 

Martin

Useful to know that about TR-KMP, it means the French aircraft retained that functionality too.

[RidgeRunner]

Yes, Wez @Wez. At least every photo I have of the Gabon machines shows the Cowl shutters, closed on the ground and open in flight

 

M

 

PS: see email

[RidgeRunner]

3 hours ago, RidgeRunner said:

Yes, Wez @Wez. At least every photo I have of the Gabon machines shows the Cowl shutters, closed on the ground and open in flight

 

M

 

PS: see email

I ckecked with Fred Borne and he confirms - all closed when on the ground

 

Martin

[72modeler]

8 hours ago, Learstang said:

So if I'm doing a USAF Special Ops Skyraider (which I am), I should just leave the cooling shutters off?

 

Regards,

 

Jason

I will check with my friend who flew them in SEA to see if they were wired open or removed.

Mike

[Tailspin Turtle]

16 hours ago, 72modeler said:

 

So, when are we going to get a big fat two-volume monograph on the F4U/AU-1? Pretty please?

I regret that as far as my scribbling is concerned, you’re going to have to settle for bits and pieces in my blogs, e.g. https://tailspintopics.blogspot.com/2017/04/the-last-propeller-pulled-corsairs-f4u.html

[Work In Progress]

3 hours ago, 72modeler said:

I will check with my friend who flew them in SEA to see if they were wired open or removed.

Mike

Removed AFAIK

[72modeler]

1 hour ago, Tailspin Turtle said:

I regret that as far as my scribbling is concerned, you’re going to have to settle for bits and pieces in my blogs, e.g. https://tailspintopics.blogspot.com/2017/04/the-last-propeller-pulled-corsairs-f4u.html

I had saved that one! Think Jim Sullivan will ever do a comprehensive book on them? Thanks for taking the time to post, Tommy!

Mike

[Finn]

So what is this little antenna to the left of A-1H for:

 

 

Jari

[RidgeRunner]

Tommy @Tailspin Turtle should know

[72modeler]

17 hours ago, Finn said:

So what is this little antenna to the left of A-1H for:

I have sent the photo to my friend who  flew A-1H's and A-1E's with the 602nd SOS, so as soon as I hear from him, I will post his reply. At first glance, I thought it might be the rod that projected to indicate whether the front cowl shutters were open or closed, but IIRC, that indicator was on the RH side of the nose.

Mike

[Tailspin Turtle]

Most later Skyraider pilots thought it was a post to hang a helmet bag on. It's really a fixed sight from once upon a time. I've got something on it somewhere...

 

That was easier than I thought: https://tailhooktopics.blogspot.com/2020/05/ad-skyraider-dive-angle-sight-post.html

Edited May 5, 2020 by Tailspin Turtle
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