IgorD Posted Monday at 08:12 PM Report Posted Monday at 08:12 PM Hello Bravo pilots. I have owned my Bravo since September of 2021 and have done a factory engine along with a complete Garmin panel. However I am wondering what is the average speed that you get. I feel that I should be getting better than 160 TAS at 70% at 6500. I had taken it up to 17k and was getting 180 TAS with same power settings. I usually fly with 23/30 settings ROP. Could it be rigging or this all you get with a Bravo? When filing a flight plan at 160kt I always end up getting better speeds than forecasted.
Rick Junkin Posted Monday at 08:51 PM Report Posted Monday at 08:51 PM @IgorD At 70%, as calculated from a fuel flow of 13.2gph LOP, I see 142KIAS at 6K' and 136KIAS at 15K. Standard day true airspeeds are 155KTAS and 171KTAS respectively. For completeness of data for comparison to yours, I run 30"/2200RPM at 13.2gph. I'm almost always near full gross at takeoff with CG at 46" +/- 0.2" My engine has about 1100 hours on it. EDIT: I have TKS as well. What fuel flow are you running at 30"/2300RPM?
IgorD Posted Tuesday at 01:26 AM Author Report Posted Tuesday at 01:26 AM 4 hours ago, Rick Junkin said: @IgorD At 70%, as calculated from a fuel flow of 13.2gph LOP, I see 142KIAS at 6K' and 136KIAS at 15K. Standard day true airspeeds are 155KTAS and 171KTAS respectively. For completeness of data for comparison to yours, I run 30"/2200RPM at 13.2gph. I'm almost always near full gross at takeoff with CG at 46" +/- 0.2" My engine has about 1100 hours on it. What fuel flow are you running at 30"/2300RPM? Running 17.5 GPH 1590 TIT. I tried to run it LOP however TIT at that FF would be at 1650 and loss of speed would be almost 15KTS.
skykrawler Posted Tuesday at 05:16 PM Report Posted Tuesday at 05:16 PM Does your bird have TKS? That'll cost a few kts, maybe 5.
Fritz1 Posted Tuesday at 05:50 PM Report Posted Tuesday at 05:50 PM my benchmarks at 17,000 ft are 185 KT TAS 2250 RPM 30.5" 18.5 GPH 1580 TIT 380 hottest CHT typically on #4 cylinder, GAMI injectors, about 0.3 GPH spread, 900h on a factory reman, I have TKS which I think scrubs off 3-5 KT, typically take off at gross, any luggage goes as far aft as possible, I tried 90% power 24/34 for short periods to see what it does, flow goes to 21.5 GPH to keep temps in check, speed increases by about 11 KT, the fastest I have gone for short periods of time with that power setting is 205 KT in 21,000 ft, sealing the baffles really helped my temps, Tempest fine wire plugs appear to reduce TIT, more complete combustion in the cylinder, extrapolating all that to 25,000 ft the TKS Bravo will probably reach 215 KT TAS with throttle and prop firewalled, fuel flow will probably go to 23--24 GPH, the highest I have taken the Bravo is 23,000 ft, boost started dropping off from 34" passing 21,500 ft, passing 22,000 ft climb was getting anemic, something like 300 ft min, sweet spot for the Bravo is between 19,000 ft and 21,000 ft, everybody believes their own press, that in mind I think this is about as good as it gets in a piston single, anything that goes any faster costs at least three times as much to operate, the weak spot on the Bravo is the exhaust, it really pays to keep TIT below 1600, I check the exhaust for cracks religiously every 25h oil change, none found so far, keep fingers crossed!
IgorD Posted Tuesday at 09:37 PM Author Report Posted Tuesday at 09:37 PM If we are going somewhere far it does make sense to go to 15-17k however my local flights 200 or under I stay at 6-8k. What do most Bravo drivers get for TAS under 10k?
hazek Posted yesterday at 07:18 AM Report Posted yesterday at 07:18 AM ~160TAS for me at conservative 65% or so ROP
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