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I recently found a Cessna 172 that had been totaled by the insurance company because of hail damage.

The PDF from that page has detailed pictures which show hail-divots all over the the wings, body and empennage.

enter image description here

Can the plane still fly like this?

What effect is this likely to have on the flight characteristic of the plane?

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  • $\begingroup$ An interesting information would be whether these planes had to land (and so where able to fly), or the damages took place on the ground. Also are you interested in "can fly" only, or also in "allowed to fly"? $\endgroup$ – mins May 6 '17 at 10:36
  • $\begingroup$ That looks to me to be cosmetic. If a mechanic will sign an annual then you can fly it. I'd check to see if Cessna has any SBs out for hail damage first, though. $\endgroup$ – acpilot May 8 '17 at 18:54
  • $\begingroup$ Of course, there is the note on the report: "PHOTOS DO NOT CLEARLY DEPICT THE HAIL DAMAGES." So I suspect it is signficantly worse than it appears $\endgroup$ – abelenky May 8 '17 at 18:55
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Like anything in aviation, it depends...

There are a lot of discussions on the internet about it you can find

Here (mooney)

Here (cessna)

And Here

It is a case by case situation and depends on the extent of the hail damage and what/where the damage occurred. In many cases the issue crops up that you can not simply bang the dents out you would need to reskin the panel. This can, depending on the aircraft be a costly process.

There are planes out there flying with light hail damage and it causes no problems, in many cases its purely cosmetic. A lot of planes flying out there have other similar damage (tool drops, bird strikes, impacts from rocks etc) and fly just fine.

An good A&P would most likely be able to tell you if the particular Cessna in question is still airworthy.

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  • $\begingroup$ @PHChilly:s answer suggested that hail damage can have adverse effects on aerodynamics just like icing. Has someone made research on this topic in wind tunnels? I would guess this is quite critical knowledge. $\endgroup$ – Communisty Jun 28 '17 at 12:43
  • $\begingroup$ I dont know of any research but if you follow the links here many people seem to agree that it largely depends and should be handled on a case by case basis. Icing substantially changes the shape of the wing and GREATLY effects CG. Hail damage does not necessarily change the wing shape that drastically and does not impact CG. $\endgroup$ – Dave Jun 28 '17 at 13:53
  • $\begingroup$ @Communisty I imagine that would really also depend on the aircraft and its performance capabilities. $\endgroup$ – Jayson Sep 7 '18 at 22:08
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I have bought, flew, and sold a couple of hail damaged planes, and adjusted claims on many more. The plane doesn't know it has hail damage and flies as it should. Good prior point regarding structural damage, that would be very bad. Dime to silver dollar size dents are no big deal. The price future sale is a bigger issue. Good luck, flyingadjuster

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  • $\begingroup$ My plane was hail dinged up back in the 70s 2 owners before me. Found out just how much when it was repainted - lot of red bondo filling the dings and smoothed out nice. Paint shop removed all that - only surface without dents was the ailerons, they think those were either reskinned or replaced. Unfortunately log books were lost after that, no data. Everything else had been filled, even the stabilator. They stripped it all, cleaned any surface corrosion, acid etched it, alodyned it, filled the dents with new lightweight filler (microballoons/epoxy mix), and will be priming and painting soon. $\endgroup$ – CrossRoads Nov 28 '18 at 17:02
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Airflow over the wing would be so disrupted that it'd be unsafe to fly, assuming it got off the ground to begin with. It might even be able to take off, but the critical speeds and handling qualities would be so far out of design conditions that you'd have no way of knowing what the airplane would do next.

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    $\begingroup$ Any sources / references? I see many online forums where posters seem to claim it is only a cosmetic issue, and doesn't really affect handling? $\endgroup$ – abelenky May 5 '17 at 16:29
  • $\begingroup$ Private Pilot 101. Same reason you're not supposed to take off with ice on the wing - any significant change in surface texture disrupts airflow, thus affecting lift, thus changing performance and handling characteristics. From the FAA Pilot Handbook of Aeronautical Knowledge (faa.gov/regulations_policies/handbooks_manuals/aviation/phak/…): "As little as 0.8 millimeter of ice on the upper wing surface increases drag and reduces aircraft lift by 25 percent." A wing that looks like somebody took a ball-peen hammer to it is going to have similar problems. $\endgroup$ – PHChilly May 5 '17 at 16:36
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    $\begingroup$ You'd be quite the test pilot going flying in an aircraft looking like that... no idea what any of your speeds are (other than, equal to or higher than what's in the POH for stall speed, equal to or lower than the POH for VNE, etc), no idea what sort of flutter issues you might encounter, no idea of a LOT of what's out there. If the alternative were certain death from flowing lava or the advancing Mongol hoard, it might be worth trying, but for anything less, there's just no way. Far too many opportunities for things to go seriously wrong. $\endgroup$ – Ralph J May 5 '17 at 16:56
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    $\begingroup$ I want to see the data supporting the divot = ice claim. VGs significantly change the surface and improve performance. Your blanket statement, like most blanket statements, is questionsble. Airworthiness cannot be determined from a few photos. $\endgroup$ – acpilot May 5 '17 at 19:21
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    $\begingroup$ I don't understand the downvotes. While I think PHChilly might be a bit on the extreme side, I have to agree with the premise. Icing adds significant weight in addition to the disruption of airflow, so there are some additional factors that make those difficult to compare, but any significant change to wing shape will have unknown consequences. I'd be less concerned with it getting off the ground than I would be with what happens if/when it encounters icing again. Or even worse, what happens when it does stall? I wouldn't want to find out that its new spin characteristics are a bit extreme. $\endgroup$ – Shawn Jun 1 '17 at 18:28
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I can tell you that hail damage does not have a significant effect on low performance aircraft such as metalized c 120s through cabin class twins unless you have structural impacts at seems in the skin. Frankly you would be hard pressed to tell the difference behind the wheel and yes even with it iced up. Your more likely to find departures from designe and test performance from poorly riged aircraft that are cross controlled before its even untied.

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