REFLECTOR: Performance

[Scott Baker]

I notice that several responders are giving numbers for a Velocity 
Standard RG, while Geoff's aircraft is a Velocity 173 (aka LW 'Long Wing').
Velocity Standard models, with their smaller wings and reduced drag, are 
faster than their 173 brethren ... by 15 knots on average (with 
comparable engines and propellers).
The factory V173FG trainer is hard pressed to see 145KTAS in cruise.  I 
think the RG version cruises between 155-160KTAS (about 15knots faster 
than the fixed gear model).
These numbers are pretty close to what Geoff is reporting for his aircraft.
Scott B.



On 5/8/2013 10:38 AM, Geoff Gerhardt wrote:
> Folks,
>
> I'm getting pretty consistent performance out of my 173RG over the 
> last 8-9 months since initial flight testing.  My question to you guys 
> is, are the performance numbers I'm seeing typical, or should I be 
> seeing better performance?  Normally, on a cross country, I'll fly b/w 
> ~8-12,000', ~60deg LOP which typically has me going 150kias at 
> 8-8.5gph.  Full power, 160kias is about my max speed.
>
> I have a fixed-pitch Catto prop (66x74, design target 200mph @ 
> 2800RPM).  When I'm doing 160kts, my prop is spinning at ~2800RPM. 
>  That tells me that I have the power to spin the prop, but may have 
> air frame drag that's keeping me from seeing the 200mph predicted by 
> Catto at 2800RPM.
>
> I have a standard 200hp, Lyc IO-360, Lightspeed EI on one side, Mag on 
> the other.  Timing as per spec for both EI and Mag.  About 90hrs on 
> the engine (rebuilt).  Compression/oil consumption is normal.  Very 
> stable performance from the engine.
>
> My plane is fully finished and pretty tight.  Main/nose gear doors are 
> not hanging out and are reasonably well tucked in when the gear is 
> raised.  Main wing angles of incidence are spot on, no rudder trimming 
> was necessary to center the ball - she flies nice and straight.
>
> The factory predicts I should be able to cruise at 175kias - that's 
> just not possible with my current setup.  Can others with Std 
> Velocities relate the performance you are seeing?  Is this as good as 
> it gets, or does anyone have suggestions for things to check to see if 
> I can eek out a bit more speed?
>
> Thanks.
>
> Geoff
>
>
>
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