carusoam Posted October 31, 2011 Report Share Posted October 31, 2011 Can anyone recommend a method for calculating / setting %hp using an iPad or other smartphone type app? Altitude, Rpm, %bhp, adjusted for temp difference from std day, with approximate FF... I am still using a laminated copy of my POH chart and interpolating old school style. There's got to be a better way to plug in the number and chug out an answer. Best regards, -a- Quote Link to comment Share on other sites More sharing options...
xftrplt Posted October 31, 2011 Report Share Posted October 31, 2011 Search the Apps for "Aircraft Power." You'll find two, one was panned in the reviews. Quote Link to comment Share on other sites More sharing options...
jetdriven Posted October 31, 2011 Report Share Posted October 31, 2011 If running LOP, add 2" of MP from the book power settings and set power with FF. Quote Link to comment Share on other sites More sharing options...
danb35 Posted October 31, 2011 Report Share Posted October 31, 2011 If running LOP, just set power with fuel flow, and ignore MP/RPM (within reason). Quote Link to comment Share on other sites More sharing options...
carusoam Posted October 31, 2011 Author Report Share Posted October 31, 2011 Dick, Thanks I'll take another look. I bought one, but did not quite get what I expected... I still use ROP and the POH data on some flights. DanB, (or anyone else) Any idea where i can look up the proper bhp% factor to multiply by FF? The Lycoming numbers for a particular compression ratio have been given several times. I have an IO550. I have calculated this factor using POH data. I would like to compare notes. Best regards, -a- Quote Link to comment Share on other sites More sharing options...
danb35 Posted October 31, 2011 Report Share Posted October 31, 2011 The multiplier depends on your compression ratio--for 8.5:1, I believe it's either 14.7 or 14.9. I know I've seen a reference posted, but I don't recall where. Lyc vs. Conti doesn't matter. Quote Link to comment Share on other sites More sharing options...
cunnira Posted November 2, 2011 Report Share Posted November 2, 2011 I bought the Power Wheel App but it doesn't come up with the same numbers as the POH. Quote Link to comment Share on other sites More sharing options...
carusoam Posted November 2, 2011 Author Report Share Posted November 2, 2011 The other one is IO-360 Power Calculator from Air Dave, LLC. It is free and covers -a, -c, -d, -j and -k engine groups. Would be nice to know how accurate the free one is? Sounds interesting, but does not cover my IO-550G needs. I sent Air Dave a request, but have not heard back.... Does anyone know Air Dave? i will share POH power chart data. I have it typed into an excel spreadsheet already.... Best regards, -a- Quote Link to comment Share on other sites More sharing options...
carusoam Posted November 2, 2011 Author Report Share Posted November 2, 2011 DanB, Comparing the numbers you gave above to my POH 14.7 or 14.9.... 15 works just as well....65% power at 12gph = 180 hp (roughly 12 X 15). Quote Link to comment Share on other sites More sharing options...
carusoam Posted November 2, 2011 Author Report Share Posted November 2, 2011 New Question on the same topic..... LOP (or peak) @ 65%bhp but compared to what? My engine max output is 280 bhp (at 2,500rpm) . It is detuned from much higher possibilities. The O3 engine max output is 310 bhp (2700 rpm) Is my O1 red box the same as the O3? 65% for the O1 is 180hp (180/280) ...from my POH and supported by using 15gph X FF... 65% for the O3 is 201 (201/310) ....Supposing here... Can I use the same 201hp and safely stay outside the red box? Has my math gotten fuzzy? Best regards, -a- Quote Link to comment Share on other sites More sharing options...
Shadrach Posted November 2, 2011 Report Share Posted November 2, 2011 Quote: carusoam Dick, Thanks I'll take another look. I bought one, but did not quite get what I expected... I still use ROP and the POH data on some flights. DanB, (or anyone else) Any idea where i can look up the proper bhp% factor to multiply by FF? The Lycoming numbers for a particular compression ratio have been given several times. I have an IO550. I have calculated this factor using POH data. I would like to compare notes. Best regards, -a- Quote Link to comment Share on other sites More sharing options...
Shadrach Posted November 2, 2011 Report Share Posted November 2, 2011 Quote: Shadrach Sent you a PM... Quote Link to comment Share on other sites More sharing options...
carusoam Posted November 2, 2011 Author Report Share Posted November 2, 2011 Thanks Ross, got it. Quote Link to comment Share on other sites More sharing options...
Shadrach Posted November 2, 2011 Report Share Posted November 2, 2011 Quote: carusoam New Question on the same topic..... LOP (or peak) @ 65%bhp but compared to what? My engine max output is 280 bhp (at 2,500rpm) . It is detuned from much higher possibilities. The O3 engine max output is 310 bhp (2700 rpm) Is my O1 red box the same as the O3? 65% for the O1 is 180hp (180/280) ...from my POH and supported by using 15gph X FF... 65% for the O3 is 201 (201/310) ....Supposing here... Can I use the same 201hp and safely stay outside the red box? Has my math gotten fuzzy? Best regards, -a- Quote Link to comment Share on other sites More sharing options...
carusoam Posted November 2, 2011 Author Report Share Posted November 2, 2011 Compression ratio for the IO550G 8.5:1 Not so surprised..... Best regards, -a- Quote Link to comment Share on other sites More sharing options...
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