My first reaction was that 9 knots seemed a lot for just some minor aerodynamic tweaks. But then I remembered that when Diamond introduced similar mods (TKS panel fits, gap reduction on baggage doors, fairings on various hinges, gap seals) on their DA42 VI, the gain was 10-15 knots.
So, Peter, smoothen out that TKS-to-wing interface and start doing direct-to Egypt!
It is certainly a marketing stunt, just like anything else coming from Cirrus.
I guess that the nine knots will come at FL250, full bore. Possibly only 5 knots at regular cruise down low? Still astonishing. But what we know is that the a Cirrus’es speed is extremely susceptible to minor things like no other certified airplane (spotlessly clean wings, flaps absolutely fully retracted, wheel wants installed perfectly, etc.).
They talk about two things: the joints between the TKS panels and the wings/control surfaces. These were previously very nice to begin with though. But it‘s definitely a key area for a Cirrus‘es cruise speed. Owners of rare clean wing SRs have often reported 5-8 knots more than on TKS aircraft, so if they got this „perfect“ now, it makes sense.
The other are the wheel pants. The have even further enclosed them towards the bottom, like they do on speed racing aircraft. Even previously, these wheel pants where quite „racy“. The new wheel pants might not be practical especially in European operations, where taxying across transitions from grass to tarmac from time to time is inevitable.
I lost nothing measurable due to TKS – unlike some who have reported a 7kt loss. Possibly because this part was done right.
The video is painful to watch – just an advert for the plane, with silly bits like someone walking up to it with skis (no ski bag… yeah, right, in a $1M+ plane?) but not carrying the rest of the ski kit 
Their speed gain claim is “up to 9kt TAS” which, translated to FL250 as Marketing always does with turbo planes, is an IAS gain of about 5kt. The video shows some vague CGI leading edge cleanup and making the hole in the underside of the wheel cowling smaller so the gap around the tyre is tighter (which will make the SR22 even better with grass and a bit of mud (not! ). 5kt is possible with a lot of small cleanups, especially if you also change the engine setting recommendation (does the POH say anything?).
Just seen Bosco’s post above – he’s arrived at the same numbers. Yes; it’s possible. Not a good idea to close up the wheel cowlings though.
I thought TKS SR22 already had a pretty clean leading edge, because the wing has a recess into which the panels fit, unlike retrofits which just go on the front and rely on the installer doing a really good job with the sealant (like I did, but it’s not easy).
One should check the POH.
The easiest way to gain those required 5kt IAS would be to extend the allowed W&B envelope a few cm further back – or even more simple to change the empty mass balance to have a CoG that is a bit further back so that at minimal load for speed measurements the CoG is further back.
Maybe the SR22 is special but I have never seen any increase like that, and when I fly alone I often fly quite rear-loaded. The plane just does the same old speed all the time: 138kt IAS at LOP 23" 2400 11.7 GPH. In theory it is supposed to be expected but (some previous threads) it doesn’t seem common – probably because we cruise way into the parasitic drag region.
The easiest way to gain those required 5kt IAS would be to extend the allowed W&B envelope a few cm further back – or even more simple to change the empty mass balance to have a CoG that is a bit further back so that at minimal load for speed measurements the CoG is further back
Maybe the case for gliders or economical aircraft? but with 310hp already in the front the only way to get +10kts is TAS/IAS with turbo or throw +30hp with +4gph and de-rate max RPM
TKS on clean wings does east cruise speeds, I never flown a clean wing Cirrus only FIKI ones, but I saw 15kts loss on a friend M20J (200hp) and some people online reported 5kts loss on M20R (310hp) from TKS retro installs, still better than airspeed loss from rime ice on the wings but surely not worth it for short cloud flying
I think there is room to grab 9kts from smoothing those TKS kinks
gallois wrote:
a PSA engine I believe the same as found in a Peugeot 106 and I believe it did Brest ,-Corsica -Brest on less than €100 of diesel.
It’s a Pennec Gaz’Aile wikipedia, official site
Silvaire wrote:
100LL is currently very slightly cheaper than premium auto fuel in my area, at $4.55/USG or Euro 1.05/liter.
Wow. That is half of what we are paying here.
Local report: Avgas at Birrfeld is CHF 2.38/Ltr (approx € 2.28) Automotive fuel (95 lowest quality) is between 1.65 and 1.80 CHF (approx € 1,70).
Jet A1 is CHF 2.03 (€ 1.95) per liter.
Those are prices which include fuel tax and VAT.
Peter wrote:
The video is painful to watch
That is so true… How in hell would you take your plane to the ski if you already live in a snowy area? And if so, would you take a Xcub for 1/3 of this price, that is able to land anywhere, or this heavy cow with a landing gear that you will have to replace, if only you can take off again…
Or that for Samedan, and you will rent a jet…
Ibra wrote:
5kts loss on M20R (310hp) from TKS retro installs,
I have seen about minus 3kts post TKS install on my bird, That included changing from a McCauley three blade to a Smaller diameter Hartzell, its insignificant when on a 3 or 4 hr flight. The mooney has a laminar flow wing. Like on gliders any change in profile has immediately a huge impact probably. If you have ever flown an hi performance glider e.g. ASW20 through a rain shower you know what that means…….I like the remote control though for the Cirrus door, for sure a good sales argument ;-) for all those new crypto billionaires………
