74657 Posted September 10, 2011 Report Posted September 10, 2011 I finally got my Missile running like it should. The family has gone on 2 cross country round-trips this week. First one from KBEH to KTVC for dinner with friends (and a quick customer call) and another one today from KBEH to KESC. With the exception of splattering a bug on my windshield @ 10,500 feet and scaring the you know what out of me everything was perfect. How does this look: 20" / 2350 RPM / 15gph (Running CHT's @ 380 and EGT's @ 1375, ROP) = TAS 176 KTS. I hate to admit it but I haven't had the opportunities to "stretch her legs" since I bought the plane last year. I'd consider running LOP but I need to learn more about how to do it. I have a brand new engine and am trying to take as good of care of it as I can. I'm trying to target the EGT and CHT temps but don't know how many degrees ROP I am running. Do these numbers sound about right for a Missile/Ovation? I tried running @ 2500 RPM and noticed a 3 kt increase at the expense of an additional 1 gph of fuel. The plane quiets down a bit... One thing I find misleading is that Rocket's website shows performance data for the Missile making 24" @ 7500 and 20" @ 12,500. I don't see how this is possible being that all I could get was 20" @ 10,500. On my trip today I climbed out @ 120 KTS which got me approx. 700-800 fpm while keeping the CHT's around 380. Fuel burn was around 20 all the way up to 10,500. At altitude it was burning 15 gph. I wanted to see how "efficient" I could be so I nosed it over into a 500 fpm descent @ 18"/2350 RPM and saw a TAS of 185 KTS @ 12gph. I fueled up on the ground and pumped 21 gallons of fuel into it. The total time in the plane was 1:25 and total distance traveled was 230 miles. I probably could have saved 10 minutes by expediting my descent and arrival but still saved 25 minutes in travel time over my old Tiger. I can't wait to take fly down to Florida this fall. These Mooney's are unbelievable machines..... Quote
carusoam Posted September 10, 2011 Report Posted September 10, 2011 74657, Gotta love a mooney with an IO-550.... One of these days allsmiles will have one and claim it to be "the best mooney ever" Check out a thread on O3 fuel flows. There was interesting information regarding fuel flow settings for different versions of the IO -550. The -G has 23 gph at t/o. http://www.mooneyspace.com/index.cfm?mainaction=posts&forumid=3&threadid=2964 To get MP OF 20" at 12,500, must have been an interesting atmospheric day. When flight testing, they must look for these special days? Best regards, -a- Quote
74657 Posted September 10, 2011 Author Report Posted September 10, 2011 Thanks for the link. We set my takeoff fuel at 28.5 gph. When I got it last year it was only 25 ish. When the engine was overhauled 2 heads had cracks. The broker I bought it from said "when you get to 400 feet you need to turn on the boost pump".......... Quote
thinwing Posted September 12, 2011 Report Posted September 12, 2011 20in at 12500 is about right..I figure a .75in manufold press drop per 1000 ft...or 9.4 in drop in this case...kpc Quote
flyboy0681 Posted September 12, 2011 Report Posted September 12, 2011 I like all the numbers except one: 15gph Quote
74657 Posted September 12, 2011 Author Report Posted September 12, 2011 How much speed will I lose if I go LOP? I have GAMI's on the engine. I'm assuming that LOP is for cruise only? Leave it ROP on the way up and down? 15 GPH is thirsty but nets me the same MPG as my Tiger did...... Quote
LANCECASPER Posted September 12, 2011 Report Posted September 12, 2011 Hopefully you mean MPG not MPH Quote
jetdriven Posted September 12, 2011 Report Posted September 12, 2011 Lean it to 30 LOP and do a 4-way flight test at 7500' to see. I'd guess you can make with an 8.5:1 C/R that should be 14.9 x FF(GPH) = HP. so, 65% power = 13.1 GPH and 75% power = 15.1 GPH. So you only gain some while flying a little slower. If you were willing to fly at J speeds you would almost have J fuel flows. The IO-550 is a ridiculously efficient engine. FWIW our J is 10 GPH at 75% power LOP (150 TAS). Actually thats right near peak. Saves maybe .5 GPH from 50 ROP and costs 5 knots. To save fuel, we cruise at 65% that is 8.7 GPH and 145-150 TAS. Much bigger difference. Perhaps someone should determine how much is saved from flying at lower % power and slower, and how much is saved from BSFC improvement from LOP. We also cannot climb LOP in a J. Low altitude you lose more performance than FF and up high, you just cannot climb well at all. Going to 50 ROP gives it a nice kick in the boot. I know Bonanza guys (Deaken back in the day, and the APS guys) can climb LOP in ther Bonanzas, just crank it to 15-16 GPH FF and stare at the CHT. Anything crossing 380, get leaner or get out. :edited for proper FF values Quote
AustinChurch Posted September 12, 2011 Report Posted September 12, 2011 Quote: 74657 How much speed will I lose if I go LOP? I have GAMI's on the engine. I'm assuming that LOP is for cruise only? Leave it ROP on the way up and down? 15 GPH is thirsty but nets me the same MPG as my Tiger did...... Quote
74657 Posted September 12, 2011 Author Report Posted September 12, 2011 Austin - We chatted last year about the fuel flow issues I had. We tried getting the fuel flows up to 30 on takeoff but couldn't get more than 28.5 without throwing all of the low/mid out of whack. There are 3 adjustments on our fuel pump and the main one requires you to remove the oil filter each time. We will live with 28.5 gph at takeoff. Our field elevation is 600 feet. With OAT's in the 80's the plane doesn't like any less than 120kts or the CHT's go 425 in a hurry. What power setting do you use on your long haul trips? I like the quietness of 2500 rpm but don't like feeding it another gph over 2350. Thanks. Brandon Quote
jetdriven Posted September 12, 2011 Report Posted September 12, 2011 Sorry to recommend leaning on the climb, I forgot the -A has autolean. Quote
carusoam Posted September 12, 2011 Report Posted September 12, 2011 Note on IO 550-G fuel flow... LOP @ 12,000' gives about 11.5 gph on my 550-G @ 2,500 rpm Probably lose 10kts compared to ROP which is about 15.5gph under the same conditions. I use the blue box ROP technique for climb and steep descent. 23gph during climb @2,500 rpm. Thankfully, the climb doesn't take that long.... Anyone care to compare these numbers to a Cirrus with IO 550? Best regards, -a- Quote
AustinChurch Posted September 12, 2011 Report Posted September 12, 2011 If I want to really move, I spin 2550 and WOT for 24.5"mp, 100 degrees ROP, 17.5 gph for a TAS of 188kts at 8500 MSL but most of the time I run the LOP settings I mentioned above. I'm surprised your CHT's are running that high. Mine runs around 325 with only a 14 degree spread between the hottest/coolest on a hard climb and around 290 in cruise. What I have to watch is the oil temp. If the OAT is above 90 and I climb at 90 IAS the oil temp will rise to 230 so, like you, I climb out at 120 IAS for similar climb performance that you're seeing and oil temp doesn't rise above 195. Quote
carusoam Posted September 12, 2011 Report Posted September 12, 2011 Austin and Brandon, What is the max rpm that you get with your missile conversions? Best regards, -Anthony- Quote
AustinChurch Posted September 12, 2011 Report Posted September 12, 2011 I'm spinning mine at 2700. The original certification was for 2650 so I called Rocket Enginering to ask why. Their response was that the FAA would not allow more than 300hp on the conversion and they found that 550's turing 2700 produced 305-310. I don't know if I buy that explanation, but I set my prop gov for 2700 a year ago and haven't looked back! Quote
74657 Posted September 13, 2011 Author Report Posted September 13, 2011 Mine was set around 2550 but I turned mine up to 2700 after having a similar conversation with Rocket. Austin - I do see the same thing you do in regards to oil temps. In my last few longer trips the oil gets up to 205 at climb and runs about 190-195 in cruise with OAT's in the low 60's. My CHT spread is close to yours, maybe a little wider @ 20 degrees across all 6 but on around 380-400. My baffling appears to be OK. All of the people that no nothing about the conversion say "this plane needs cowl flaps." Those comments get me hotter than my cylinder heads. Any thoughts? Fuel flows are verified to be correct, the baffling isn't torn or ripped at all. Quote
PTK Posted September 13, 2011 Report Posted September 13, 2011 Quote: carusoam One of these days allsmiles will have one and claim it to be "the best mooney ever"- Quote
Seth Posted September 13, 2011 Report Posted September 13, 2011 Brandon and Austin- Thank you for all of the valuable information on the Missile - Be ready, becasue I'll be PMing both of you a lot in the future regarding the Missile - I should finally go up and get it toward the end of September - the newly overhauled engine should be installed mid next week. Take care, -Seth Quote
Parker_Woodruff Posted September 13, 2011 Report Posted September 13, 2011 Quote: allsmiles In all honesty NO. I will never purchase a Missile or a Rocket. I don't believe on modified airplanes. Especially Mooneys. I'm of the opinion they detract from the inherent value of an excellent stock airplane. This goes with most all modifications with the exception a very few such as redoing the interior and some avionics, SOME avionics upgrades. The best Mooney ever imhp is the stock J. Period. Quote
RJBrown Posted September 13, 2011 Report Posted September 13, 2011 Quote: allsmiles In all honesty NO. I will never purchase a Missile or a Rocket. I don't believe on modified airplanes. Especially Mooneys. I'm of the opinion they detract from the inherent value of an excellent stock airplane. This goes with most all modifications with the exception a very few such as redoing the interior and some avionics, SOME avionics upgrades. The best Mooney ever imhp is the stock J. Period. Quote
PTK Posted September 13, 2011 Report Posted September 13, 2011 It's not a matter of faith in quality. It's strictly a matter of value. Quote
74657 Posted September 13, 2011 Author Report Posted September 13, 2011 Quote: Seth Brandon and Austin- Thank you for all of the valuable information on the Missile - Be ready, becasue I'll be PMing both of you a lot in the future regarding the Missile - I should finally go up and get it toward the end of September - the newly overhauled engine should be installed mid next week. Take care, -Seth Quote
carusoam Posted September 13, 2011 Report Posted September 13, 2011 All smiles, I understand your opinion towards the Missile conversion, and I was not very specific. However, I was describing the Mooney engineered and constructed Ovation. It is much like the venerable M20J, but slightly enhanced..... As for the missile conversion, that's what got me interested in the IO 550 to begin with. (probably my first question on this board, years ago) Best regards, -a- Quote
74657 Posted September 13, 2011 Author Report Posted September 13, 2011 Allsmiles - How does a Missile or Rocket negatively effect the value of an airplane? Do you mean in terms of re-sale or aquisition or a reduction in "efficiency" because of the larger engine? I paid more for my Missile than any comparable J was listed at. In terms of performance, it is equal or better than an Ovation and is ~35-50AMU's less. Nothing against the Ovations, I would have loved to landed in one but the Missile was in my price range whereas the O was at the top and would have left me with little reserve for any upgrades. I think for the money, a Rocket or Missile will give you more bang/buck when compared to an Acclaim/Ovation if you are talking about speed/efficiency. Quote
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