Rotax 916 iS

[pylotttt]

Has anybody put a Rotax 915 IS or 916 iS in an RV yet?

160hp at altitude would probably really move (compared to my Lycoming o-320).

 

[AeroEngineer]

916? Probably too soon (but who knows).

915? At least one: https://www.vansaircraft.com/first-flights/robert-haags-rv-4/

 

[hpmicrowave]

Rotax 916

The 916 &915 are awesome engines but the max horsepower is time limited to roughly 5 minutes by the fadec for takeoff and climb. Cruise power drops back to around 141 to 143 horse power. But with its turbocharger and fadec system it’s good to 15k before the computer starts limiting max boost/power. But this is still significant engine power as compared to a standard Lycoming at the same altitude.

 

[warmi]

Once they get it to 180 hp for take off/climb and 160 hp continuous it will most likely become market leader for both low and mid range HP applications.

Rotax 917is perhaps ….

Btw.
There is already “enhanced” 916is being offered with 180hp with lower 1200 hours TBO (and obviously no support or warranty from Rotax ) by a third party …but I would personally wait for the official Rotax implementation


https://shop.edgeperformance.no/pro...p-boxer-motorer/ep917ti-180hp-turbo-efi-fadec

 

[AeroEngineer]

Btw. There is already “enhanced” 916is being offered with 180hp with lower 1200 hours TBO (and obviously no support or warranty from Rotax ) by a third party …but I would personally wait for the official Rotax implementation
https://shop.edgeperformance.no/pro...p-boxer-motorer/ep917ti-180hp-turbo-efi-fadec

The little that i know about Edge Performance is what I read in this Kitplanes article, which was overall very positive. Interesting reading if you're interested in the possibility of higher-power Rotax engines:

https://www.kitplanes.com/on-the-edge/

 

[rsr3]

My experience of EP engines in the glider towing world… Steer clear!

 

[CaptPausert]

I thought about trying the 916 in the RV-9 I am building but the $50,000 price tag combined with no one providing any FWF support currently killed it. There is also the issue that I spoke to one of the guys at Vans and apparently someone put a 915 in and had yaw divergence issues due to the extended cowl to get the W&B right. I decided that it was too much money and time to get it working. Especially when an A&P friend of mine offered an overhauled O-360 for about $25K. Even if I add the FlyEFII system 32 I will still be over 20K less when you consider the cost of a custom cowl and firewall forward stuff.

 

[David Paule]

In addition to the destabilizing effect of the longer cowl, moving the prop forward is also destabilizing. These affect both the longitudinal and directional stability.

Dave

 

[AeroEngineer]

915? At least one: https://www.vansaircraft.com/first-flights/robert-haags-rv-4/

Ok; Two:

https://www.kitplanes.com/lockwoods-rotax-powered-rv-9-debuts/

https://vansairforce.net/community/showthread.php?t=218868

In addition to the destabilizing effect of the longer cowl, moving the prop forward is also destabilizing. These affect both the longitudinal and directional stability.

According to the VAF link above, they seem to have added a dorsal fin. If they're finally unveiling this airplane, presumably the flight tests have been promising.

 

[JMyers1]

The 916 &915 are awesome engines but the max horsepower is time limited to roughly 5 minutes by the fadec for takeoff and climb. Cruise power drops back to around 141 to 143 horse power. But with its turbocharger and fadec system it’s good to 15k before the computer starts limiting max boost/power. But this is still significant engine power as compared to a standard Lycoming at the same altitude.

As far as I know the computer does not do this, it's on the pilot to pull back power. Also I believe the 15k is just the critical altitude of the turbo.