I understand the exterior finish of the F-117, partly responsible for its small radar signature, was extremely fragile. Apparently it breaks down in sun light or perhaps merely open air?

The F-117 has been retired, replaced by the B-2, F-22, and F-35. Does any of these "stealth" aircraft incorporate more durable finishes without that finish sacrificing "stealthiness?" Is any of their finishes impervious to sun light that they can be used in service without any need for special hangars or covers when not flying?

OR, what are the service lives of the finishes in service? How easily can their radar absorbtion renewed or replaced. Were the F-35 in use on an aircraft carrier to ensure a no-fly zone in Iraq, for example, would aircraft force the carrier's return to renew or replace the finish more frequently than what is currently the duration of carrier duty for a similar purpose?

These planes are not the only military items to have the special coating...the subs do too. The UV rays break down the surface of this special coating over time..but it takes awhile and it is not easily replaced. It would be easier to just replace the sheet metal entirely. Besides aircraft and subs, there are other military applications utilizing it. I will not go into details on what the coating is or how it is applied. I doubt there is anything out there that would be better for the intended purposes.

I'd like to buy a gallon and paint my Jag.

Woodrow:

I thought nearly all exterior surfaces (skin) is now non-metallic composite. If this is accurate, or close to accurate, replacing sheet metal might not be a solution to renewing the finish.

If the finish is that difficult to renew, is it reasonable to infer that a large number of less sophisticated stealthy aircraft might be more useful in service than a small number of super-duper aircraft? What I suggest is that stealthiness is more important for aircraft survival than being an egregiously superior aircraft like F-22s because when an F-22 loses its stealthiness, is it still egregiously superior to all other aircraft? And we have so few of them. So how long and how much to return that F-22 to its superiority?

Considering continuing cost overruns, the F-35 does not appear to be that modestly priced stealthy aircraft.

The coating on the skin is moderately resilient. The tricky part with stealth is sealing the joints. On the F-117, they used an epoxy paste that took several days to cure fully. This doesn't seem like a giant deal, but on a true stealth aircraft, they seal all the access panels too. So general maintenance time goes way up versus a non stealth aircraft. In the 90s they switched to a tape (it wasn't really a tape, but that's the best description I can think of) that drastically reduced the time involved in replacing a panel. The F-22 and F-35 are designed with many less access panels, and they put them in less signature critical places, like accessing through the internal bays.

The trade off for reduced signature is much higher maintenance. Something like a hail dent can completely alter the stealth characteristics.

Composites are used a lot, but certain areas just need metal. Those coatings have to be maintained. Shape has to be maintained. And integral to each composite panel is a mesh that absorbs some of the energy that isn't diverted. This has to be maintained. Lots of stuff going on to stay invisible as long as possible

It's the air power equivalent of scent-lok clothes. More expensive, different maintenance, but any edge can make the difference.

Several years ago Jeff Cooper wrote about a "friend" in the Air Force who gave him some "radar scrambling paint"He painted his Mercedes + drove the speed he wanted to.

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Originally posted by NormanConquest:
Several years ago Jeff Cooper wrote about a "friend" in the Air Force who gave him some "radar scrambling paint"He painted his Mercedes + drove the speed he wanted to.

Now we just need a paint that diffuses laser reflections.

Grizz

Re: the F-35, here's an article about the coating.

https://www.wired.com/2012/11/f-35-gets-stealthier/

"Lockheed’s O’Bryan told reporter Tirpak that the F-35’s advanced technology will reverse this trend of gradually eroded stealth. In contrast to old-style coatings, “the conductive materials needed to absorb and disperse incoming radar energy [on the F-35] are baked directly into the aircraft’s multilayer composite skin and structure,” Tirpak reported, citing O’Bryan.

Over time the JSF’s skin will settle, O’Bryan boasted, making it even smoother and more radar-evasive — all without any of the expensive upgrades required by previous stealth planes."

thing about single issue wonder weapons like the F 117, B2 and F35 is, somewhere out there, some scientist is working overtime to develop a countermeasure and when he does, your wonder weapon is useless. Only F 117 shot down in combat was by the Serbs with obsolete technology .

https://theaviationist.com/201...7/vega-31-shot-down/

Grizz

Cooper also told about a couple of local yokel cops who set up a speed trap outside the A.F. base.Seems that when they turned on their radar to harrass the public that the missiles (unarmed of course) attacked the squad car within breathing space.They (the cops) were told not to anything that stupid again.DUH!!! Radar seeking missiles. Gotta LOVE it.

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Originally posted by Idaho Sharpshooter:
I'd like to buy a gallon and paint my Jag.

For the most part the color of turkeys is not pigment but refraction. Would that scatter the radar ?? If so we can glue turkey feathers on the plane !!

From what I hear the F35 has so many problems that it rarely leaves the hanger. Radar evasion is probably low on the priority list. I won't ruin my day by looking up the cost over runs. I hope Trump will introduce some simple business principals to government.

Dave

Ah yes. Let us indeed hope so. Lets give a buisness man a chance. We have seen what career polititions can do who have no concept on monetary value except their salary.

quote:

We have seen what career polititions can do who have no concept on monetary value except their salary.

And pensions, and healthcare coverage, and on and on....