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Just checked the SB list on the Cirrus web site. The winterization kit SB is up. No data on cost, but it is an OWNER/OPERATOR installable option! Looks pretty simple to install as well. Two inlet restriction plates and a POH insert.
Unfortunately (for me), it appears that the winterization kit is only for SR20s with the landing light in the lower cowl.
Those of us with the light in the inlet area are out of luck on this one, I think. [:(]
Interesting design for the cooling kit. Cooling kits normally involve plates over the oil cooler to raise oil temperature.
This kit obstructs cooling air from entering the cowling. This kit design should result in a significant decrease cooling drag and an increase in cruise speed. Be interesting to see what really happens.
Bob
TurboWx
Received kit yesterday for my 22. Cost is $100, initial installation (owner approved) estimated at 1.5 hr. Only two screws needed to remove or reinstall each inlet cover once initial installation is complete. Comes with two placards:
"Remove when outside temp. is above 32 F. "
“Not for A/C w/landing light in cowl inlet.”
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Those of us with the light in the inlet area are out of luck on this one, I think.
Steve,
Since the winterization kit seems to involve two inlet restriction plates… and you have a light in the inlet area… (follow me on this)… seems you already have a sort of mini-winterization kit… perhaps you call call it a Winterization Kit Light. [:P]
- Mike.
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Since the winterization kit seems to involve two inlet restriction plates… and you have a light in the inlet area… (follow me on this)… seems you already have a sort of mini-winterization kit… perhaps you call call it a Winterization Kit Light.
True, but if I remember right, someone deliberately flew once on a hot summer day with the landing light removed and it did not help the cooling issue - in fact, that was you, wasn’t it?
So I am assuming that having the light in place will not really help much in the winter, either.
I was hoping to be able to use the winterization kit - especially for the reasonable price of ~$100 which has been bounced around the forums. In cruise last night for example, my oil temps never got above 130 - which I know is too low, but there’s not much I could do about it!
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Winterization Kit Light. [:P]
Shouldn’t that be Winterization Kit Lamp? [:P]
Walt
What happens if the light is burned out???
iIt would be nice if the kit was adjustable, like cowl flaps, that could be closed at altitude, open on the ground.
My cht’s run in the low 200 at cruise, oil below 150. In climb out, cht’s go to low - mid 300s & I wonder if the winterization kit will make them go a lot higher
John
N468JP SR20 #1261
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True, but if I remember right, someone deliberately flew once on a hot summer day with the landing light removed and it did not help the cooling issue - in fact, that was you, wasn’t it?
Steve,
It was. I admit to being more focused on the pun than on the facts with the “Winterization Kit Lite” (better spelling, anyway).
Cirrus has always maintained that the landing light in the inlet does not substantively affect the cooling; I decided to try a couple of back-to-back flights in very hot summer conditions in the desert southwest, with and without the landing light in place, and noted no measureable difference.
In fact, in certain applications, a restriction is used to accelerate and aim the flow - like a carefully positioned thumb over the end of a garden hose, or the restriction designed into these SR71 engines.
I don’t know enough about fluid dynamics… but I think that the restriction must be something other than flat - like the slightly rounded surface of a landing light - to have this effect. The faster the airflow, the ‘sharper’ it needs to be. I think.
- Mike.
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I admit to being more focused on the pun than on the facts with the “Winterization Kit Lite” (better spelling, anyway).
And I admit to missing your pun in the first place! [:$]
Anyway, I just got an email from Mike Prince who says that the winterization kit (#70027-002 ) WILL fit SR20s with the landing light in the inlet, and that the SB will be revised to reflect this. Great news! [:)]
Steve
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What happens if the light is burned out???
Harrell,
Ah… now you’ve touched on poorly-understood and seldom-discussed topic of Dark Drag. Dark Air presents more drag than Light Air - counter-intuitive, since everyone knows that Dark Air also provides less lift. [;)]
- Mike.
So can I be a junior member of the COPA Response team now (can be called on for ad hoc crisis)?
And can I get a badge or anything that the real guys get if I am just a junior member?
Flying will tell but I doubt it very much. The SR20 and 22 are way overcooled for most flying. However, because they have to pass cooling tests for certification in hot and high conditions it must be designed to that end of the operating spectrum.
Looking at that stiff carbon fibre oil service door bulging 3/8" in flight I can only imagine what the pressure differential is from the upper to lower cowling. There is a LOT of air going in there!
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The SR20 and 22 are way overcooled for most flying.
Maybe the SR22… but certainly not the SR20. I flew an early SR20 for almost three years, and it was a constant challenge to keep CHTs under control in the climbout in hot weather. I’ve heard reports that the improved cowling (it has since been modified to improve cooling) is better, but CHTs still demand attention in the summer.
My SR22 CHTs run about 50 dF cooler than my SR20 CHTs did.
- Mike.
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Looking at that stiff carbon fibre oil service door bulging 3/8" in flight I can only imagine what the pressure differential is from the upper to lower cowling. There is a LOT of air going in there!
Help out a mechanical and physical dunce here: Wouldn’t it be the reduced pressure as a result of the rapidly moving airflow over the cowling cause the oil access door to bulge, not the pressure from inside?
Maybe saying “most flying” was an overstatement. However, keeping CHT’s under 450f in climbout on a hot summer day is at the end of the operational envelope that I’m talking about.
That’s why they invented cowl flaps!
To-MAY-toe / to-MAT-oh.
The cowling stuffs air into the upper deck of the engine/cowling plenum . The air flows through the cylinder fins, the oil cooler, leaks etc and into a lower pressure area of the lower cowling. The nicely faired air exit shrouds on the lower cowling provide a nice low pressure source to suck the air out. The air MASS is the same but the relationship between pressure and velocity is inverse from the top to bottom of the cowling plenums.
The differential between the upper and lower decks of the engine is measured in inches of water on a manometer. As I recall, the spec calls for 5’’ to 8" of water drop.
The relationship of pressure versus velocity versus air mass etc is complex but suffice to say that you want to keep a high pressure and lower velocity on the upper deck to allow time and density for proper and even round-the-cylinder cooling. Too fast and the cylinder is inadequately and maybe unevenly cooled and ends up with a circumferential crack at the point where the barrel screws onto the head, among a hundred other possibilites.
The addition of the cowl ring on early radial engine installations clearly demonstrated the value of pressure cowlings. The ramped inlets of low drag cowlings such as those by Lo Presti, experiental Lancair’s, Swearengen rely on similar principals also.
So, it is desirable to have high upper deck pressures.
However, in the case of the SR22, the upper deck pressures are such that the oil service panel is pushed out at pressures higher than those being exerted on the exterior of the upper cowling. I can’t give you an exact figure but the streamlined cowling and airframe of the Cirrus is not likely to create any significant negative pressure.
The solution is not to nessecarily reduce those high pressures, just secure the door better. It might be hard to accomplish though on the cored and flanged composite door in existing cowlings. With such a big leak sealed up, the inlets could be significantly reduced in size though, and thereby reduce cooling drag.
That’s just my opinion though, I may be wrong - Dennis Milelr
Well, I asked![:)] I think you lost me somehwere between “oh.” and cowling plenums. Thanks for trying, but while you may be able to teach an old dog new tricks, you certainly can’t teach a dumb one anything.
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The solution is not to nessecarily reduce those high pressures, just secure the door better.
Couldn’t this be tested pretty easily by duck taping the underside of the oil door before a flight and observing temps vs an untaped door? Of course, that’s if the extra pressure doesn’t blow the door off completely!