Elisha 1 #1 December 20, 2005 OK, I know several of you are pilots, but I'm sure most of us aren't. I'm pretty sure that Otter's, King Air, Skyvan and CASA's are all twin turbine's (and others, but these seem to be the most common jumpcraft). What kind of engines are on your typical Otter vs KA vs Skyvan vs CASA? People keep talking about how Mike Mullins has the fastest KA around since he puts bigger engines on his KA, so what are regular KA engines (as in HP) and what does he have? What about this new Monterey KA? What do Otter's usually have - they seem to climb pretty slow in comparison? What about Skyvans/CASAs? What are a Cessna Caravan? That is a turvine engine isn't it, but it is single engine? How many HP? I think the PAC 750XL is a 750HP engine, so I guess the PAC's is more powerful (besides superior plane design). Quote Share this post Link to post Share on other sites
voodew1 0 #2 December 21, 2005 An otter has -20s a Super Otter has -27s a wicked super otter and the Pac 750 have -34s those are Pratt and Whitney engines I believe a Caravan has a -27 Most Skyvans have Garretts but some have P&W I am not sure on the horsepower but the higher the number the more horsepower The pimp hand is powdered up ... say something stupid Quote Share this post Link to post Share on other sites
PhreeZone 15 #3 December 21, 2005 The PT6a-X(Xis the 20,27,34) series engine is rated at shaft horsepower. The -20 is rated at 500HP and the 34 is rated at 750. Mullins has -34's on his bird. -27's are pretty common on most Otters since -20's take about 20+ minutes to get to altitude and -27's are more in the 15 minute range. -34's are becoming more common (Aerohio's crashed otter had them, Fayards got at least 1 bird with them, and a few others are out there) but they are not common yet. I think the Caravan has a different series since its exaust is only on one side unlike the normal turbine thats on both sides but its at 675 HP. Climb rate is balenced by HP, weight of the plane, weight of the cargo and a few other factors. An Otter with -34's will climb slower to altitude then a King Air with -34's since for starters the King Air is hundreds of pounds lighter and is carrying at least 8 less people. Then again worn out -34's will climb slower then new -27's from my understanding. As Voodew says.. Garretts are on most Skyvans and CASA's and all I know is they are said to be a PITA Yesterday is history And tomorrow is a mystery Parachutemanuals.com Quote Share this post Link to post Share on other sites
FrogNog 1 #4 December 21, 2005 The Cessna Caravan has one or two variants of the Pratt & Whitney PT6A engines. The major difference is a single-side exhaust, which will hurt horsepower to some degree. I think one of the variants of the PT6A used by one of the Caravans (not sure if this is old Caravans, or new Caravans, or only Grand Caravans, or what) is the PT6A-114, which I hear is like a PT6A-135 (with a single-side exhaust) but with a PTA6A-41's fuel control system. (Not sure what's special about the -41's fuel control.) The PT6A-135 is apparently like a PT6A-36 with a different gearbox and higher cruise rating, and a -36 is like a -34 but with higher ITT limits. I think the single-side exhaust on the Caravan's PT6A-114 cripples it so instead of 750 HP (as one might expect from a PT6A-135), it can only produce 600 HP. I want to stand up for the Caravan, because it's my favorite plane so far. I'm not ready to concede that the PAC 750 XL is a "superior plane design" in so few words. It's just a plane that is better suited for hauling jumpers profitably to altitude when time, fuel cost, and aircraft cost are taken into account. The Caravan may be slower and more expensive but it wasn't badly designed - like the PAC Cresco, it just wasn't designed specifically for skydiving. The PAC Cresco's original design purpose appears to be more compatible with skydiving lifting. Now, if someone wants to say "superior skydiving plane design", I'm fine with that. Also, "more economical skydiving plane design" would be good. -=-=-=-=- Pull. Quote Share this post Link to post Share on other sites
bob.dino 0 #5 December 21, 2005 I still prefer doing 4-way from a Caravan as opposed to an XL. The door is nicer... Quote Share this post Link to post Share on other sites
mcdizzle 0 #6 December 21, 2005 QuoteThe Cessna Caravan has one or two variants of the Pratt & Whitney PT6A engines. The major difference is a single-side exhaust, which will hurt horsepower to some degree. I think one of the variants of the PT6A used by one of the Caravans (not sure if this is old Caravans, or new Caravans, or only Grand Caravans, or what) is the PT6A-114, which I hear is like a PT6A-135 (with a single-side exhaust) but with a PTA6A-41's fuel control system. (Not sure what's special about the -41's fuel control.) The PT6A-135 is apparently like a PT6A-36 with a different gearbox and higher cruise rating, and a -36 is like a -34 but with higher ITT limits. I think the single-side exhaust on the Caravan's PT6A-114 cripples it so instead of 750 HP (as one might expect from a PT6A-135), it can only produce 600 HP. Are you a pilot? Just curious where you get your info from. The caravan is available with 2 versions of the same engine. A PT6A-114 (600 HP) or the PT6A-114A (675 HP). The better performing otters in skydiving have -27 or -34 engines on them. -27 are factory and are rated for 680 HP but derated to 620 HP. -34 engines are rated at 750 HP but when fitted to an otter, are still only allowed to produce 620 HP (wing structual limitation). The only advantage to this is that you have more available horsepower all the way up during the climb (available horsepower decreases with altitude in turbine engines). Bigger engine numbers have nothing to do with horsepower, as does placement of the exhaust "crippling" the performance. Quote Share this post Link to post Share on other sites
Eule 0 #7 December 21, 2005 QuoteI'm pretty sure that Otter's, King Air, Skyvan and CASA's are all twin turbine's (and others, but these seem to be the most common jumpcraft). What kind of engines are on your typical Otter vs KA vs Skyvan vs CASA? I have some info on what engines these aircraft had originally, but your mileage may vary. From "Jane's Encylopedia of Aviation", published 1980, updated through 1993. shp = shaft horsepower (used to turn the prop); ehp = equivalent horsepower (shp + thrust from exhaust). de Havilland Canada DHC-6 Twin Otter First prototype flights May 1965 First 230 built (Series 100 and Series 200) with PT6A-20 engines From spring 1969, Series 300 with PT6A-27 engines 613 total (all series) delivered through June 1978 (Skydive Dallas just put new engines on their yellow Otter a few weeks ago. I _think_ they put on the PT6A-34 engines instead of the stock -27 engines but I'm not sure.) There seems to be a bunch of King Airs... Beechcraft King Air Model 90 Introduced September 1970 A90, B90 models C90 version has PT6A-21 engines @ 550 ehp 1227 total (all models) delivered through April 1978 Beechcraft King Air E90 PT6A-28 engines @ 550 ehp (derated from A100 engines) 61 built as US Navy T-44A with PT6A-34B @ 750 hp Beechcraft King Air Model A100 Introduced September 1971 PT6A-28 engines @ 680 ehp 275 total sold by April 1978 Beechcraft King Air Model B100 Introduced March 1975 AiResearch TPE 331-6-252B engines @ 715 shp Beechcraft King Air Model C100 Announced October 1977 PT6A-135 engines @ 750 shp Beechcraft Super King Air 200 First prototype flights October 1972 PT6A-41 engines @ 850 shp Some built as military C-12A with PT6A-38 engines @ 750 shp 318 private, 113 miiltary by early 1978 Beechcraft Super King Air 300 First flown 1981 PT6A-60A engines @ 1050 shp Beechcraft Super King Air 350 First flown 1988 Replaces Super King Air 300 no engine info Shorts SC.7 Skyvan First prototype flights January 1963 Series 1 - Continental engines Series 1A - Astazou II engines Series 2 - Astazou XII engines Series 3/3A/3M/Skyliner - Garrett-AiResearch TPE 331-201 engines @ 715 shp 127 sold by mid-1979 There are several CASAs, but I _think_ the jumping one is the C-212. CASA C-212 Aviocar First prototype flights March 1971 Garrett-AiResearch TPE 331-5-251C @ 750 shp 136 sold by 1978 CASA C-212-10 In development about 1980 Garret-AiResearch TPE 331-10 @ ? hp QuoteWhat are a Cessna Caravan? That is a turvine engine isn't it, but it is single engine? Yes, single engine turboprop. Cessna Model 208 Caravan I First flown December 1982 Model 208A: PT6A-114, 600 shp Model 208B and Grand Caravan: PT6A-114A, 675 shp This book isn't new enough for the PAC 750 XL, but since that's in current production, you can go look up the specs on their site. EulePLF does not stand for Please Land on Face. Quote Share this post Link to post Share on other sites
justinb138 0 #8 December 21, 2005 QuoteSkydive Dallas just put new engines on their yellow Otter a few weeks ago. I _think_ they put on the PT6A-34 engines instead of the stock -27 engines but I'm not sure.) Bingo! Quote Share this post Link to post Share on other sites
Elisha 1 #9 December 21, 2005 Thanks guys, this is nice info. So...if the KAs and Otters have similar engines, I assume that the Otters are so much slower since they are heavier and carry more (heavier plane plus more weight from jumpers)? So what's with Mullins's KA being faster than everyone elses? Does he have something bigger than 34's? What about the Beech-99 (e.g. Lodi's) - that thing climbs fast? Also, what is the range of engines usually used on C-182s? From what I hear, the stock engines can really only get the plane up to about 9-10K and I know that I've been close to 14K before in a 182. Quote Share this post Link to post Share on other sites
BillyVance 34 #10 December 21, 2005 QuoteThanks guys, this is nice info. So...if the KAs and Otters have similar engines, I assume that the Otters are so much slower since they are heavier and carry more (heavier plane plus more weight from jumpers)? So what's with Mullins's KA being faster than everyone elses? Does he have something bigger than 34's? No... I believe it's because he gets the most performance out of his engines than most pilots are willing to do... Then again, Mullin's King Air is one of the most efficient out there, because he made it so... That guy has more air time in the pilot's seat than just about anybody else in the sport, plus he's also a captain for Fed Ex during the week. "Mediocre people don't like high achievers, and high achievers don't like mediocre people." - SIX TIME National Champion coach Nick Saban Quote Share this post Link to post Share on other sites
PhreeZone 15 #11 December 21, 2005 Look at the engines, Mullins has -34's with a beefed up super structure to hold them, not sure if any other King Air has that combo. He also has 4 bladed props vs most jump planes 3 bladed which if I understand correctly will increase the effecency of the props. Mullin's plane is not your everyday King Air, its fairly customized. The one that used to be in FL at Space Center used to be fairly close from my understanding. Not sure if thats the one thats in CA now or if someone else has another King Air out there.Yesterday is history And tomorrow is a mystery Parachutemanuals.com Quote Share this post Link to post Share on other sites
billvon 2,435 #12 December 21, 2005 >He also has 4 bladed props vs most jump planes 3 bladed which if I >understand correctly will increase the effecency of the props. Not really. In terms of takeoff/climb efficiency, a 1 bladed prop is ideal - but outside a few ultra high performance sailplanes, no one uses them. 2 blades is most common because they are mechanically fairly simple (and it's very easy to make fixed pitch 2 blade props!) and pretty efficient. More blades = slight loss in low speed efficiency, but they can spin slower and impart the same thrust (more lifting surface) which is a big deal at high speeds. When you hit the higher airspeeds, the tips come very close to the speed of sound (which = horrendous efficiency!) A multi-bladed prop can help reduce tip speed to well below mach 1 while keeping the same level of thrust, at only a slight increase in overall drag. A final reason for multi-bladed props is that the prop disk is smaller, and thus landing gear height can be reduced for a given engine power/thrust. Quote Share this post Link to post Share on other sites
2fat2fly 0 #13 December 21, 2005 QuoteGarretts are on most Skyvans and CASA's and all I know is they are said to be a PITA Garretts are noise machines that happen to produce thrust.I am not the man. But the man knows my name...and he's worried Quote Share this post Link to post Share on other sites
FrogNog 1 #14 December 21, 2005 No, I'm not a pilot in any practical sense of the word. My info on the -114 being available in a Caravan came from the web. On the one hand, the web is an unreliable source because it doesn't have certain conventional accuracy-building motivation behind it. On the other hand, some parts of the web do have conventional accuracy-building motivation behind them, such as selling people jet engines. I was told by one of our pilots that the single-sided exhaust versions of the PT6A, made to make nose-mounted engine use more convenient, caused a horsepower crippling effect. I didn't and still don't have any way to determine if the apparent size of that effect (20%, in this case) was reasonable. Is the single exhaust port on PT6A engines so equipped larger in size than each twin exhaust port on "normal" PT6A engines? -=-=-=-=- Pull. Quote Share this post Link to post Share on other sites
FrogNog 1 #15 December 21, 2005 QuoteQuoteGarretts are on most Skyvans and CASA's and all I know is they are said to be a PITA Garretts are noise machines that happen to produce thrust. They make so much noise it scares the air away. This provides thrust. The thrust can be reversed to slow the plane after touchdown. -=-=-=-=- Pull. Quote Share this post Link to post Share on other sites
pilotdave 0 #16 December 21, 2005 Check out http://www.pwc.ca/en/3_0/3_0_1/3_0_1_2_2.asp for info about every version of the PT6A. There are a LOT of versions. Dave Quote Share this post Link to post Share on other sites
FrogNog 1 #17 December 22, 2005 QuoteCheck out http://www.pwc.ca/en/3_0/3_0_1/3_0_1_2_2.asp for info about every version of the PT6A. There are a LOT of versions. Dave It has stats, but it lacks the "why" information. Why does this version exist? What versions is it based on? What special advantages does it provide? Is it obsoleted by any other version(s)? Is it still available new? Not that anyone _needs_ to provide that info, but it would help us understand more about the rockets we ride to altitude. It beats only learning about your plane when the parts fall off in your hand. -=-=-=-=- Pull. Quote Share this post Link to post Share on other sites
gravitysucks 0 #18 December 22, 2005 QuoteI still prefer doing 4-way from a Caravan as opposed to an XL. The door is nicer... I've been lucky enough to jump the Otter, Supper Otter, King Air (including Mullins'), and the Caravan in my brief career, and must say that the Caravan is by far my favorite turbine. Nothing beats a creative 4-way exit off the Cessna though, dino! Quote Share this post Link to post Share on other sites
riggerrob 561 #19 September 9, 2014 PT6A-114 and -114A engines are only built for Caravans. The single-stack exhaust is unique to Caravans. I forget Cessna's original logic, but it had something to do with keeping fumes out of the cabin and not setting the belly baggage panier on fire. The first time we saw a single exhaust on a PT6A was on a helicopter. Now Blackhawk salesmen tell us that since PT6A-114 was originally designed to produce only 600 horsepower , it's breathing is limited by the exhaust. To solve the breathing problem Blackhawk offers up-grade kits that include more-powerful versions of PT6A with the more popular double exhaust. Quote Share this post Link to post Share on other sites
theplummeter 14 #20 September 9, 2014 billvon>He also has 4 bladed props vs most jump planes 3 bladed which if I >understand correctly will increase the effecency of the props. Not really. In terms of takeoff/climb efficiency, a 1 bladed prop is ideal - but outside a few ultra high performance sailplanes, no one uses them. 2 blades is most common because they are mechanically fairly simple (and it's very easy to make fixed pitch 2 blade props!) and pretty efficient. More blades = slight loss in low speed efficiency, but they can spin slower and impart the same thrust (more lifting surface) which is a big deal at high speeds. When you hit the higher airspeeds, the tips come very close to the speed of sound (which = horrendous efficiency!) A multi-bladed prop can help reduce tip speed to well below mach 1 while keeping the same level of thrust, at only a slight increase in overall drag. A final reason for multi-bladed props is that the prop disk is smaller, and thus landing gear height can be reduced for a given engine power/thrust. Four bladed props on the King Air series were used primarily to increase drag for landing and reverse. We have two B200 King Airs with identical engines (-42s) but different props. The three blade is quieter and faster in cruise. At one point the four blade prop and a couple other things were marketed and sold as part of a "short field" package by Beech. Quote Share this post Link to post Share on other sites
potatoman 0 #21 September 10, 2014 A little off topic, but my dream ship would be: Top wing, with dehidral, similar wing to the PAC, but a bit longer. Twin diesel engines, turbo charged, 700Hp each 3 rows of seats, Tailgate. Why? Top wing design is just more stable(CG is low), and dehidral offers stability. Diesel engines are not yet so explored in "larger" aviation, but they do perform much better at altitude, and economical. Twin engines, safer, faster climb. 3 rows of seats and tailgate......Thats just me.You have the right to your opinion, and I have the right to tell you how Fu***** stupid it is. Davelepka - "This isn't an x-box, or a Chevy truck forum" Whatever you do, don't listen to ChrisD. Quote Share this post Link to post Share on other sites
dzswoop717 5 #22 September 10, 2014 To answer your question about the 182 engines. The 182's we use for skydiving are mostly the older models that came from the factory with a Continental o470 230hp engine. These are the 182's that on average take 20 minutes to get to 10,000ft. There are several different engine upgrade mods for the 182 airframe. I won't get into every name and how they achieve the hp but there are mods to increase hp to 260, 275, 285, and 300. There is also a blower available that can be added to a stock 182 that allows the engine to maintain it's hp to a much higher altitude thus increasing it's climb performance without increasing the cubic inches of the engine. If you add wing extensions and other stol mods you can get a 182 to climb at super otter speeds. If you are paying for the mods you can easily end up with over $100,000.00 invested in an old 182. Quote Share this post Link to post Share on other sites
riggerrob 561 #23 September 10, 2014 ***A little off topic, but my dream ship would be: Top wing, with dehidral, similar wing to the PAC, .... 3 rows of seats, Tailgate. Why? Top wing design is just more stable(CG is low), and dehidral offers stability. ..... 3 rows of seats and tailgate...... ............ We can agree on some of those points. I like high wings because the cabin floor is usually lower, making them easier to load. I like tailgates because they are easier to exit. I also like Skyvans because they allow me to stand on my hindlegs. Erect posture makes a big difference when you are carrying a 55 pound tandem rig and a 200 hundred pound student. As for high wings being more .... just be careful about adding too much extra dihedral (ala PAC 750) because too much dihedral will create Dutch roll. Have you ever noticed that the big military transport planes (C-5, C-17, C-141) all have high wings and negative dihedral? Quote Share this post Link to post Share on other sites
riggerrob 561 #24 September 10, 2014 .... Twin engines, safer, faster climb. .... ............................................... You and I are going to have to "agree to disagree" about twin engines being "safer." Light twins require precise piloting skills IMMEDIATELY after one engine quits. If the engine quits on a Cessna, Kodiak, PAC 750, Porter, etc. the pilot only has one decision make: which field to land in? Quote Share this post Link to post Share on other sites
potatoman 0 #25 September 10, 2014 With jumpers moving like they do, they'll probably cancel the dutch roll. (And would a see through bubble like window in the floor not be cool for spotting)You have the right to your opinion, and I have the right to tell you how Fu***** stupid it is. Davelepka - "This isn't an x-box, or a Chevy truck forum" Whatever you do, don't listen to ChrisD. Quote Share this post Link to post Share on other sites
