Flaps up Vs. Flaps Down.....Not on the ground!!!

Hi kik, the P51 Mustang, as a popular example when parked would have dropped flaps due to the hydraulics design. After the plane was parked the system pressure would bleed away and the flaps would lower. Not all planes do this but that is an example of one situation where dropped flaps would be a correct representation of that particular plane.

Cheers....Snowy.

Every photo I have seen of a parked F4U has the flaps down. Also I have been to Osh Kosh many times ahd they all had flaps down when parked. There was a self closing step on the right inboard flap section which was used to get on the wing then into the cockpit.

Dave

Can't confirm other aircraft, but I worked around the three T-28B's of the ACE Board while stationed at Ft. Bragg, and it was standard procedure to leave the flaps deflected to 40% when they were on standby because of the hydraulics issue, also the steps to get up on the wing were on the inboard left flap.

On off days, & nights, when all the "Remove Before Flight" banners were dangling in the breeze, the flaps were fully retracted, mainly to make it less subceptable to wind. There was a handle in the left side of the fuselage that released the flaps, and when they were getting ready zip the plane up, I remember watching the Crew Chief's pull this handle, then lift the flaps back into their retracted position. When the Pilots came out to do the pre-flight, Chief would have them in a down & dirty configuration, including the speed brake.

kik36, if it were me, if the Corsair was going to be displayed with the gear down, canopy open without a pilot, I'd position the flaps down.

Frank

No doubt about it - flaps down!!

I'm with you kik...It not a big deal.Like Pix says,"Build what you like, like what you build" But i guess it is big issue for competition.

Most aircraft will have the flaps down to enable the ground maintenance personnel to inspect the operating mechanisms and to check for damage and corrosion. The flaps carry quite an airload when lowered in flight and can be subject to cracking structure and leaking hydraulic actuators.

The Pilatus PC 9's ( same as a Texan 2) that I work on have this problem, from a fleet of 40 odd, most will lose hyd pressure over time. Some a/c drop their flaps within hours of shutdown, others can take a week or so, or, in a few cases, not at all! So it depends on the state of the hydraulic components, check valves/air in the system etc.
Really it will vary from aircraft type to type.
On a similar subject, Hawker Hunters will lose pressure and the airbrake will droop, same on Harriers and to a lesser extent on Hawks.
The only way to be sure is to check photo's of your type, and the specific aircraft you are modelling, to be really sure.
Pete

Hey Pete,

Speaking of the PC-9 (and T-28B), here's a picture that was made over Ft. Bragg the day the ACE Board was looking for possible replacements for their aging "Trojan's".



Take care,
Frank

Yeap if i were you i would drop the flaps on that model, it will look much better, i dont know how the flaps sistem works on that plane but i can tell you that in the Cessna 500 is a good choice to leave the flaps in a 15° position when on the ground to keep the excess of stress in the wiring. You may want to check this video, may be helpful for you.

http://www.zenoswarbirdvideos.com/F4U.html

Good look and show us when it is done
My best regards
Hector.

Over the years, I've had the good luck to maintain a couple of P-51's. When the 51 was designed and built, there were no thermal relief valves put into the hydraulic system. The only relief valve was in the selector valve, which only relieves pressure coming from the pump. In a system without thermal relief valves, you shut the engine down and 1000 psi remains in the system. On a very hot day, the pressure will build up until a line breaks or o-rings in a cylinder starts leaking. So the NAA engineers put a dump valve in the system to relieve all pressure on the system. Its operated by a T handle in the base of the panel between the pilots knees. The flight manuals instruct the pilot to pull the handle out at the shut down at the end of each flight. With no pressure on the system, the weight of the gear doors and flaps causes them to drop gradually.
When you start the beast up, you have to remember to push the handle in or you get no hydraulic pressure.

Along the same lines, one thing that makes me unhappy, is the depiction of WW II and later military aircraft with the control surfaces "repositioned". If a squadron commander should spot an aircraft left unattended with the control surfaces unlocked, someone, the pilot in command, the crew chief or mechanic is in deep do do. And if the aircraft is damaged in a storm and the surfaces are not secured, you are now talking court martial. About the only time the control surfaces are not secured are during the preflight inspection and if maintenance is being performed.

I don';t know what all the "flap" is about! I think some aircraft take on a "different" character when everything is down and dirty. It's just natrual to want to build them that way whether it's "aviationally'" correct or not! I've actually seen an F/A-18 with one flap down and another up after sitting on the ramp a few hours. Go figure! I'd wager there are a lot of throttles in the wrong position sitting on the ground! Gentleman! Check your cockpits!

Basically, it all depends on how you want to display your model! Quency's right; if the aircraft is tied down out on the ramp, the control locks should all be in place and no control surface deflections, but in the same light, if the aircraft is being displayed while in hot refuel, or while the Pilot's out taking a whiz, or when the CE's pouring over her, the control surfaces will be deflected.

Bottom line; It all depends. I've been around Aviation since I was 14, both Civilian and Military, and had the privilege of operating both fixed and rotary wing aircraft. If it was a Holiday or something like that, yes, all the aircraft are going to be zipped up, but, on an average weekday, you can find aircraft in every configuration imaginable! Again, it all depends on how one chooses to display their model.

Frank

Great info everyone.....I do remember working on a T-28, and the owner dropping the flaps so I could step up to the cockpit, that was years ago. The field I am now deals mostly with civil aviation, only once in a while does an older warbird drop by. And generally, we don't keep planes around the shop long enough to see hydraulic leaks of that nature. Also flaps for genral aviation (ie Cessna 182, Bonanzas, Pipers, Mooneys) are either electrical or mechanical, which is what confused me, I didn't realize that the older warbirds used hydraulic flaps. Thank you everyone for your sound advice and info.

Just for the record, I have decided to go ahead and model the F4U-2 with the flaps DOWN....Thanks again everyone!!!

Don't hate me but I believe an F4U-2 would have it's flaps up in a parked position. The way a pilot or crew member would get into the aircraft is by crawling up the low point on the back side of the inverted gull wing. The film I have shows the pilot scrambling up the back of the wing and the flaps are in the up position.

Later model Corsairs had a step built into the inner most flap. Flaps were left in the down position so the pilot or crew member could crawl up and into the cockpit.

Thanks A lot Weebles, right when I've made up my mind too!!!! LOL Well, I just ordered a couple of books from squadron to use for reference. I'm going to model whatever I have in my references. Is there any chance that film you have is online, or downloadable?? I would really like to check that out!!

Hello Heath,
The film I have is from a friend who flew with VMF-214. Both the History Channel and Discovery Wings made documentaries on the 214 and I believe both include film of the 214 doing a scramble.

If you go to the following web site and click on the "E Fighter Productsions" tab you'll find a photo showing a an early Corsair with the pilot about to crawl into the cockpit. As you'll see the flaps are in the up position which is the only way for them to get up there on this model.

http://www.f4ucorsair.com/

Curious, are you going to lengthen the verticle stabilizer or is there a kit for this?

David, thanks for the awesome reference!!! At this time I am just gathering references. I am building the Tamiya 1/48 F4U-1/2 for the USMC group build that ends in July. At this point I haven't researched enough to know exactly what you mean by lengthening the Vertical Stab. Hopefully Tamiya thought of that for me, eh?! LOL, I also ordered the Eduard detail set, and a new resin seat for her. So right now, I've just been admiring the clean casting that Tamiya always seems to pull off for me!!! Any hints, suggestions, ideas, etc are always welcome, and if you have any info, please don't leave me in the dark!!!! LOL

Hello Heath,
My bad. Actually it is a taller tail wheel assembly like that of the F4U-1A and D variants. So the bottom line is that the tail just stands a little taller than the F4U-1 Birdcage. Other adjustments you need to make are as follows...
1. Delete right outboard 50 cal. This was done to permit the installation of the wave guide (whatever that is).
2. Add flame hiders which are included in the kit.
3. Do not use antenna masts. There were none on this variant.
4. Do not use wire antennas. Instead there is a small whip antenna just aft of the cockpit.
5. There are two radio altimeter antennas under the fusselage.
6. Land based F4U-2's (Marine) had the tail hook removed to reduce weight.
7. Make sure you bore sightthe guns to 250 scale yards pointing slightly upward. If you actually try doing this I suggest professional help. LOL.... you would never notice it in 1/48 scale.

Tamiya doesn't provide F4U-2 cockpit detail. It has standard -1 instrumentation. I don't know of any after market kits. But here's some information I got from a reference with respect to cockpit modification...
1. The radar control panel-containing the radar switch, the scanner selector, the operating switch and the tuning switch is on the starboard side (of what I don't know, meaning on the dash, right consol, etc.).
2. The radio support panel, aft of the pilot, is completely filled with radar equipment.
3. The radio equipment is beneath the pilots seat.
The A-B stage switch, with which the scope is changed from sweep (Stage A) to gunsight (Stage B), is directly outboard of the throttle, and can be released with the left thumb without removing the hand from the throttle.
4. The instrument panel: a) the PPI scope is placed at the top center; b) the altitude instruments are on either side of the scope; c) the needle ball is below; d) the secondary instruments are grouped with navigation on the port side of the panel, and engine on the starboard; e) dials are skeleton-numbered, with most of the intermediate numbers omitted. If you model that last one you're my hero!
5. Lighting: a) indirect red, with perfect rheostat control; b) black felt anti-glard outer panel. I wonder if you could light up the cockpit with some sort of red fiber optic light! Now I need professional help!!! :-)

After market kit wise I would strongly suggest Aires 4070 which is the F4U-1 full blown engine, cockpit, wheel well and gun bay set. 74 resin parts and 46 photo etched parts. Damn thing costs more than the kit! It's a work of art!

If you're getting Detail & Scale Vol. 55 you'll find some nice drawings in there and a little history of the aircraft.

This should be enough to keep you busy! Let me know if you have any other questions.
Dave

Damn Dave, you've been busy!!! LOL Well, the Tamiya kit does include and state the two bottom antennas, as well as leaving off the mast, but I don't see the whip antenna in the directions....I saw that detail kit, but opted to just choose the eduard (due to budget constraints), but I have been seriously thinking about perhaps an open panel F4U in the future to show off the guns, and engine. I did order an engine kit, but am going to save it for the future!!! Oh, also the Waveguide is a primative form of radar, and they removed the outboard gun to equalize the weight. You should join us for the USMC build, it ends in July. Thanks for the info, I'll definately keep you in mind when I need help. BTW, great cockpit shot!!!

Hi Heath,
I have one reference that says that they removed the gun to balance the airplane, and another that refers to a secret document that says they did it for installation of the wave guide. LOL. I guess all that matters is that you remove the gun.

I'm in the middle of the project from hell right now. For several years I've been working on a 1/48 80' Elco PT Boat. I'd like to finish that project before I jump into anything new. But I'll think on it.

I'm a private pilot. Recently I started flying a Diamond Eclipse. This is an airplane that you "strap on". When you get into this airplane you sit high in the cockpit and have an unobstructed view of the world. I had the same feeling when I crawled into this FG-1D. It was opposite of what I had expected because of the size of this airplane. But sitting in the cockpit you felt like you strapped on the airplane. It feels much smaller than it really is, even though you can stand straight up with your feet on the bottom of the fuselage. I would love to fly it! I guess I better start buying those power ball tickets!

Best of luck on your project.
Dave

Guys, A wave guide is a circular or rectangular pipe that connects the radar's
transmitter and receiver to the antenna. It's measurements are specific to the
frequency of the radar unit. Wave guides can also be rigid or flexible or a combination
of both. Whatever the installation requires.
Ray