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#11
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![]() "One's Too Many" wrote in message om... If I were rich enough to afford a twin, I would like to buy a P337 Skymaster, not a 3xx or 4xx. Nasty wing AD hammer about to drop on the heads of the owners of Cessna "conventional" prop twins. Oh, and if I win the lottery, the only other Cessna twin I'd have would be a Citation of course :-) A P337 is essentially a twin engine Skylane; a 300 or 400 series is a cabin class plane. |
#12
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![]() "Dude" wrote in message ... Hmm, You raise an interesting point. Why is it that no one is making those planes anymore? Does everyone want turbine singles and twins instead? I have seen that convrting the 421 to a turbine is becoming popular. I know that turbines are safer than pistons, but I always believed that the difference in accidents between the turbine and piston twins was more a matter of training than engine reliability. Training and experience are definitely factors ("Professionally" flown vs owner flown) but an engine failure, under the same circumstances, in a piston popper might well be no big deal in a turbine. I can't say for sure, but I don't think all that many piston engines have full feathering props. Add the complexity of mixture control (and even carb heat in some) and there's more work when that much more frequent failure occurs. |
#13
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![]() "john szpara" wrote in message s.com... A couple more commander questions. My best case scenario has the following parameters: 1. Cruising speed 200+ kts (not just at the flight levels) 2. cabin class 3. potty 4. pressurized 5. price around $150k, +/- 20k 6. ceiling above FL240 Do any Commanders fit the profile? The Commander's don't fit that, but neither do the 421's...not in that price range (not one ready to fly without putting a lot more money into it to make it airworthy, or one right up against engine OH). |
#14
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#15
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On Wed, 31 Mar 2004 08:00:07 GMT, john szpara
wrote: A couple more commander questions. My best case scenario has the following parameters: 1. Cruising speed 200+ kts (not just at the flight levels) 2. cabin class 3. potty 4. pressurized 5. price around $150k, +/- 20k 6. ceiling above FL240 Do any Commanders fit the profile? Those are tough requirements, but most are commensurate with a cabin class twin. 1. Most planes (short of the low drag homebuilts) are going to have a difficult time hitting 200kts (without running the engines at 100%) below 10,000 ft. Flight levels and turbo are the way most airplanes reach 200+ kts. As an example, I fly a Seneca II. Below 10,000, the fastest you can go with 75% power is 175kts. At 20,000 75% power gets 190kts. Seneca's don't perform like the 3/4 series Cessnas, but the concept translates. The 3/4 series twins will probably do 190kts below 10k, and 220 in the 20s. 2, 3, 4. The 4 series Cessna twins meet all these requirements. 5. 150k is the LOW end of the range for the 3/4 series twins. Most are listed with asking prices from $150 to $500k. Most in this price range have high time engines, worn paint and interiors, and old avionics. A cheaper alternative would be the Cessna T310Q or T310R. Similar performance - 6 seats but without the pressurization and potty. $150k will buy a nice one. 6. The pressurized 3/4 series Cessna's have ceilings from 25-30k feet. Keep in mind that the purchase cost of these twins is in relative terms quite low. If a 421 was produced today, it would easily cost $2M. (A 2004 Baron 58 is $1M). Operating/maintenance/insurance/hangar costs on a 20-30 year old cabin class twin can approach $400/hr. Also, have a look at http://www.factoryengines.com and look how much a rebuilt GTSIO520 for a 421 costs. $50k! As others mention - the upcoming wing spar AD is a serious issue. Many shops put the compliance cost at close to $50k. Some additional info can be found he http://www.twincessna.org/ http://www.aopa.org/whatsnew/regulat...incessna2.html http://www.cessnatwinssparcorp.org/ -Nathan |
#16
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Do some advanced research on fuel required and pax load before you buy.
(play with sample weight and balance for the loads you anticipate carrying) If you want to fill the seats, your fuel load will be significantly reduced to avoid overgross. Short legs may not get you the performance you are looking for. john szpara wrote: A couple more commander questions. My best case scenario has the following parameters: 1. Cruising speed 200+ kts (not just at the flight levels) 2. cabin class 3. potty 4. pressurized 5. price around $150k, +/- 20k 6. ceiling above FL240 |
#17
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![]() "Tom Sixkiller" wrote in message ... "Dude" wrote in message ... Hmm, You raise an interesting point. Why is it that no one is making those planes anymore? Does everyone want turbine singles and twins instead? I have seen that convrting the 421 to a turbine is becoming popular. I know that turbines are safer than pistons, but I always believed that the difference in accidents between the turbine and piston twins was more a matter of training than engine reliability. Training and experience are definitely factors ("Professionally" flown vs owner flown) but an engine failure, under the same circumstances, in a piston popper might well be no big deal in a turbine. I can't say for sure, but I don't think all that many piston engines have full feathering props. Add the complexity of mixture control (and even carb heat in some) and there's more work when that much more frequent failure occurs. AFAIK all piston twins have feathering props. You probably meant autofeathering though. Most of the safety difference is probably training and the reliability of turbine engines. If you are ten times less likely to have an engine failure, you are a lot less likely to have and engine failure related accident. Mike MU-2 |
#18
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![]() "Dude" wrote in message ... Hmm, You raise an interesting point. Why is it that no one is making those planes anymore? Does everyone want turbine singles and twins instead? I have seen that convrting the 421 to a turbine is becoming popular. I know that turbines are safer than pistons, but I always believed that the difference in accidents between the turbine and piston twins was more a matter of training than engine reliability. Its both. The relability of turbines is probably 10x greater than piston engines so even if the pilots were the same, turbine accident statistics would be a lot better. Mike MU-2 |
#19
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I don't think anything fits all those requirements.
Mike MU-2 "john szpara" wrote in message s.com... A couple more commander questions. My best case scenario has the following parameters: 1. Cruising speed 200+ kts (not just at the flight levels) 2. cabin class 3. potty 4. pressurized 5. price around $150k, +/- 20k 6. ceiling above FL240 Do any Commanders fit the profile? John Szpara Affordable Satellite Fiero Owner 2-84 Indy Pace cars, 86 Coupe, 88 Formula 3.4, 88 Coupe, 88GT |
#20
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![]() "Mike Rapoport" wrote in message ink.net... "Tom Sixkiller" wrote in message ... Training and experience are definitely factors ("Professionally" flown vs owner flown) but an engine failure, under the same circumstances, in a piston popper might well be no big deal in a turbine. I can't say for sure, but I don't think all that many piston engines have full feathering props. Add the complexity of mixture control (and even carb heat in some) and there's more work when that much more frequent failure occurs. AFAIK all piston twins have feathering props. You probably meant autofeathering though. I hadn't even thought of auto-feather, but I was under the impression that most piston twins wouldn't go to full feather (it's been 15 years since I flew a piston popper twin). Most of the safety difference is probably training and the reliability of turbine engines. Agree, but I'd say that loss of a piston engine would be much more hazrardous than losing a turbine under the same circumstances (weather, load, etc.) since a turbine usually has much more power available in the remaining engine than a piston. And, yes, under high loads, the margins are equally BAD. If you are ten times less likely to have an engine failure, you are a lot less likely to have and engine failure related accident. Indeed, but, too, SEROC in a piston is possibly a negative number, while in a turbo-prop it might be 800-1000fpm. Handled the same way, I can see that what is a landing short of the runway in a piston twin would be a non-issue in a turbine. I wonder how big the gap is between the two types, from Vsse to Vsi/Vso (not sure I'm phrasing that right). |
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