Jimmbbo

Thanks for proving my point... the airplane engine is designed for its operating environment - long duration at constant RPM, the auto engine for its ever changing speed, start and stop... Similar things that do different jobs... sorta like a plow horse and a quarter horse... both are horses, but I wouldn't expect a quarter horse to pull my plow for long...

Sport_Pilot

The problem is that the maintenance requirments are huge. Because they are so antiquidated they don't enjoy the benifits of electronic ignition, computer controls, or unleaded fuel. The certification process is too expensive and restrictive. Because of this cars can go 50,000 miles or almost 1000 hours and usually much more without maintenance. Now I don't recommend this as a maintenance schedule, but I would say many if not most recieve no maintenance other than oil changes till it misses or quits. Aircraft on the other hand cannot go more than 300 hours without new points and plugs. Yes I know the plugs should be checked and the points replace every annual or 100 hours. But this fact also means the automobile ignition system is more reliable. The same goes for the fuel system. Even the oil is inferior, but that is because of the leaded fuel, detergent oil cannot be tolerated.

Wood propellers have very little flex, that is why the break instead of bending. Nicks have little to do with flexing. To boot the cars drive shafts and axles have similar flex, and are not dampened by air. As I said the flex is noting like sidestepping the clutch on a car, and most can take a fair amount of this abuse. That said there is a problem with many reduction drives, but much of this is due to the radial load and poor design.

Sport_Pilot

Obviously you missed my point. If you took an automobile engine and ran it like an aircraft engine it would last longer than it does now. The larger automobile engines would last longer than the aircraft engine, the smaller ones about the same. This is due to their superior cooling system and unleaded fuel. If they just put cooling fans on the aircraft engines and closed up some tolerances they would probably be better than that.

APIA

What tolerances? Both types have virtually the same tolerances. That is if you are talking about internal tolerances..... I would like to see how long a car engine would last running at 75% for 2000 hours.... A nick in a propeller blade is where propeller blades break, (kind of like scoring glass to break it) I will look for the link that I saw that shows how much propeller blades flex in all flight regimes, both wood and metal.

Sport_Pilot

I couldn't get the info form Aviation Consumer as I no longer have a subscription. The article was over ten years old and I wonder if they would still have it on their site? Tempted to resubscribe. I hope to fly full scale again someday.

However I did google this up.

http://www.magma.ca/~ocbc/comparat.html

As I recall Aviation Consumer pegged all GA flying at about the same as this. But IFR flying was much worse, and VFR flying was between that of a motor cycle and a car. I recall that AC converted reported statistics to the same factor, passenger hours I believe. If converted to miles it puts GA in a better light. I see a "not invented here" attitude from the GA industry and FAA toward bringing some of the auto tech into GA aircraft. Surely they would benifit form electronic ignition, fuel injection, and computers. I think EPA would have to get involved to get them to rid leaded fuel.

Sport_Pilot

I recall the ring gap and piston to cylinder gap is wider in aircraft due to running hot when sitting at the hold line. Or so it was explained to me by an old A&P mech. I could be wrong, but they seemed wide, but then again the cylinders are generally much larger. This from a conversation while helping him rebuild an aeroclub aircraft. He was a VW fanatic also, and he thought they should have some small fans for those occasions.

Ed Toner

I think the pilots of many of these homebuilts are low time types, and they constitute a large percentage of the accidents.

This reminds me of the Beech Bonanza, a very safe aircraft, the Cadilac of private aircraft. They became known as "Forked Tail Doctor Killers", because many MD's bought them. They had more money than piloting ability.

I know one personally. He told me he almost killed himself a few times so he sold his Bonanza and bought a yacht.

He lived happily ever after.[8D]

Sport_Pilot

Ahh, Beechcraft lost a lot of money when it was found that the tails were literally falling off. They also had to reinforce all of the existing aircraft with a cuff to keep the leading edge of the v tail from fluttering.

APIA

The Good old "V" tail Bonanza has killed many folks, Some pull the wings off of them, or tail, usually by exceeding the aircrafts limitations. This is a nice airplane that can do a lot of things well, however, It is not an invincible aircraft. The other one I continue to see is loss of control due to tail heavy conditions. The fuel cells on this model are forward of the CG, loading the airplane without this consideration will ultimately be a hand full or uncontrollable. It might be balanced when you leave but will be a surprise at your destination. Some of the older Bonanzas had a very complex fuel system, if the system is not understood this usually ends up in the fuel starvation column.

Sport_Pilot

Yet somehow it has a poor safety record. Yet somehow the t tail version and those which had the tail cuff AD performed on them have a good safety record. Yet the same people are flying them. Face it aircraft are dangerous, some more than others. Yes training can help you to beat the statistics, but those same people are likely also beating the automobile safety statistics.

Ed Toner

Thanks for enlightening me on this matter. I had no idea. I am not a light plane pilot. To me, the B-727 was a light plane.

I retired on the L-1011 in 1987.

The last "craft" I flew was the Paraplane. That was pure fun, and safe. I leased them by the hour. Tom Snyder was the designer and manufacturer. I heard he bought the farm in a warbird, ran out of fuel.

I noticed a lot of his demo's took off with less than a full tank. I always insisted my tanks were topped off to full.

I've accumulated close to 20,000 hours over my 34 years of flying, never an accident. Though I never blew a tire flying Banshee's off the WASP, I blew one on a B-727 landing on standing water at CLE. Hydroplaned, turned off the anti-skid to stop. No NOTAM or warning from the tower.

http://www.airdisaster.com/user-uploads/its_smoke.gif

Sport_Pilot

LOL, well reasonably so. IMO the worst problem with GA is IFR flying. The rules and instruments are too complex for those who are not staying proficient (and too many do not), and too many planes flown IFR just do not have enough performance to be safe when caught in bad weather. IMO any airplane that cannot climb 1500 or so FPM and do not have two alternators should be VFR only.

BTW - The flying doctor theory was started by Beechcraft, at least according to some lawers. Finally somebody in the FAA got smart and simulated the V tail on a shaker in a wind tunnel to find the problem, the leading edge of the tail was not secured to the fuse, the ribs were simply attached to the spar and only the spar was attached to the fuse. When it failed the leading edge would flap up and down until it failed, the down (or up) force from the failure often broke the tail cone off! Lawers used the flying doctor theory against Beechcraft to great success convincing juries that they knew about this, which is why they came out with the t tail version (the Debonaire?). I don't know if this is true or not, but I guess the juries thought it was. I think it alsmost put Beechcraft under till bought by Rayathon.

Ed Toner

I spent 3 years instructing in the T-34 at NAAS Saufley, 1959-1962. That was a Beechcraft, too, but it could really take punishment.

One structural failure caused one half the stab/elevator to fall off. The instructor landed it safely. I had the task of helping the Beech engineers find the cause. It was because of pressures during steep turn stalls during cruising configuration and excessive "G"s.

This caused buffeting on the stab., that eventually caused the failure.

west6008

I think that private pilots should routinely practice full deadstick landings.

If you go to the NTSB aviation website

http://www.ntsb.gov/ntsb/month.asp

You'll be amazed at the botched forced landings
where people hurt themselves in light planes that
have good glide ratios.

I taught my son RC flying at age six, and like all of us, made hundreds of forced
landings with models.
Now he has a Commercial license, and I hope if he is faced with a forced landing that his RC experience will help.

APIA

When I was knee high to a grasshopper and used to fly with my dad, He would expect me to have a landing area "picked out" at all times. He would chop the throttle and ask me where we were going to land. It seemed that I always picked the freshly plowed field and this would result in a broken airplane. He would then say this is where I would land and it would be a nicely manicured meadow. I guess experience is always your best teacher, paying attention to your surroundings helps a bit too.

Rv7garage

My Feedback: (10)

Sport Pilot--

I'm laughing my *** off at the #5 cause of death in your link:

[sm=spinnyeyes.gif][sm=bananahead.gif]

LIVING(ALL OTHER FORMS OF DEATH) !!!!!



Ha! I knew it would kill me some day...[8D]

Jimmbbo

Perhaps you failed to properly present your argument While your opinion is noted, I see no reason to accept it as fact.. can you point to any data to support your argument?

Common sense convinces me that running an auto engine (designed for stop and go, spurts of high power, hours of low power operation) at 75% power for 2000 hours would result in higher wear than a similarly run aircraft engine point designed for such service... auto engines simply aren't desinged for such duty..

A parallel is that Lycoming took their excellent, reliable T55 turboshaft engine from the CH47 Chinook and added a fan to make it the ALF 502 turbofan engine for the BAe-146.... For the first several years, engine failure rates were so high that airline maintenance departments were convinced that BAe meant "Bring Another Engine"...

Quarter horses don't make good plow horses...

Jimmbbo

The Bonanza is not a Cessna... Meaning that the Cessna (let's use a Turbo 210) has very strong stability in all three axes, which keeps it pointed straight, but it has a truck-like control feel. The Bonanza is much lighter on the controls, but the price for that is less stability than the 210.

A common Bonanza accident scenario involves someone who has a fair amount of total time, usually in Cessna or Piper airplanes up to a 182RG or Cherokee 6, an instrument rating and recenly bought or checked out in the Bonanza as a "move up" (frequently the new owner is a doctor or lawyer - a thread for another day). The pilot blasts off and finds himself in IMC or VMC in a dark night in an unfamiliar area, becomes absorbed in looking at the charts to figure out where he is or reviewing the chart for the approach in use, while the airplane slowly banks into a 1g spiral... Suddenly the pilot looks up, sees the airplane in an extreme nose down unusual attitude, yanks the yoke back and pulls the wings off at 5-6gs.

When I was doing Bonanza checkouts, students were doing this with such regularity that I included it in my training syllabus... If they wish to avoid becoming an NTSB statisitic, pilots are best served by understanding the strengths and weaknesses of any airplane they fly, and accomodate those weaknesses with additional training, skill or knowledge. The point is that for most pilots the Bonanza is a significant step up in performance and it requires more piloting skill and knowledge than simply reading the POH and jumping in.

Jimmbbo

Finally, one thing we sort of agree on!! But that's OK - gonna take issue on the second...

Fying in the IFR system requires more practice than 6 hours 6 approaches in 6 months or an Instrument Competency Check... Think I'd put in a 6/6/90 day or ICC requirement. Have been flying "in the system" for over 20 years, and if I take a two week vacation, my situational awareness notably deteriorates upon my return (snide remarks concerning my baseline skills not necessary )... and I am "in the system" 90 hours a month - how about the "doctor" whose prime focus is his medical practice, flies maybe 8 - 10 VFR hours a month and doesn't keep his IFR skills sharp?

As far as the airplanes are concerned, they are fine for IFR flying if the pilot understands weather, the capabilities of their airplane, and always has an "out". Lets fly a C172 into two situations. First, into known moderate icing conditions that exist from your cruise altitude to below the minimum enroute altitude - likely outcome? Declaring an emergency as you can no longer maintain altitude and descend below the MEA. Second - We'll fly into an area of forecast possible icing conditions where the MEA is below the freezing level by 3000 ft. Likely outcome? Picking up some ice, descending to a lower (warmer) altitude, melting the ice and pressing on. Since the airplanes were the same, the difference was the pilot exercising knowledge, judgement and skill.

In the late '70s, Flying magazine's Richard Collins bought a C172 to demonstrate that over a long period (one or two years as I recall) a GA airplane flown by a competent pilot could accomplish all the magazine's missions, do so as reliably as the airlines and at a savings in time and money.... I believe he proved to be successful on all counts.

See post #68 for the "flying doctor" scenario... While not limited to doctors, I've seen it first hand, and it is real... The IFR workload in a single pilot Bonanza is very high, and warrants a higher level skill.

One reason the Debonair (conventional tail Bonanza) has better accident stats is that it has more vertical fin area and is less prone to a minor upset causing the 1g spiral mentioned in my earlier post. Beechcraft suffered about the same as all the other GA manufacturers due to large number of shotgun lawsuits I mentioned in an earlier post...

APIA

Jimmbbo..... Very Well Said.

Jimmbbo

The original 2x20 gal main tanks were forward of the spar... The earliest Bonanza (-35 thru -35G) systems were very user-unfriendly, especially if they had the optional 20 gal aux tank in the baggage compartment. Using the aux tank could cause CG problems (but none that would cause the airplane to become uncontrollable if the airplane was within CG limits to begin with) if it wasn't burned as soon as you leveled off (aux tanks may be used only in straight and level flight)... It also limited the volume of baggage that could be carried.

The mid-production Bonanzas (-35H thru -35M) had 2x20 gallon mains forward of the spar and 2x10 gal aux tanks in the wings aft of the spar, which also needed to be burned as soon as you leveled off...

Fuel management on these airplanes required a good understanding of the system and attention to it. Fortunately, over the years the design of the tanks and indicating system was refined to be as as simple as any modern high performance single. From the 1961 N model on, the fuel was contained in two wing tanks (LH and RH), and two separate fuel quantity gages were installed, minimizing the aux tank and fuel quantity management problem.

Having just under 1000 hours in the C, J, P, A-36 and V-35 airplanes, I would own one in a heartbeat if I had a need and the $$. One of the nicest flying airplanes I have ever flown, and safe if it is flown properly.

Flyfalcons

Jimmbbo is absolutely correct regarding single pilot IFR flying in high performance GA aircraft. I don't think I've ever been a better instrument pilot than when I was flying 135 single pilot IFR in a Twin Cessna. I flew an average of four days and 20 hours a week doing this, and the consistent flying is what kept me flying safely. I started doing that job with over two thousand hours of flight time, with an ATP and my CFI ratings. Contrast that to a new aircraft owner who rarely flies IFR, venturing out in the weather with his new high performance aircraft and a few hundred hours of 172 time under his belt, and you can see why some high performance planes end up in the dirt. The weather doesn't make exceptions for less experienced and trained pilots; we're all flying in the same conditions.

Jimmbbo

Am reminded of the oft printed aviation poster with the biplane planted in a tree saying that aviation is unforgiving of the slightest error... IMO, aviation is neutral.. it cares not if you live or die. It rewards you with another flight if you do your job, but will gladly kill you if you screw up...

ShoestringRacer

I will agree that IFR flying is the most difficult challenge to a non professional pilot and mainting IFR currency is difficult. But your statement that any plane without 1500 FPM climb should be VFR only is absurd. You state: "just do not have enough performance to be safe when caught in bad weather" I doubt you fly single pilot GA IFR at all because that statement reflects some sort of yahoo barnstorming mentality with respect to IFR flying: as if to imply barreling into bad weather willy-nilly then needing some super powerful machine to get out of it. Well, that whole mentality is wrong. One, even if you could climb a small light plane at 1500 fpm + and you are in convective weather being able to climb in a convective cell wont do you much good once you get in it. If that is the case then why have airliners been brought down in convective weather and windshear?? Loss of control - overstressing the airframe and exceeding its limits - is what kills pilots in that situation or just a close proximity to the ground in the latter, not a lack of climb ability. And if you think power is the answer to icing encounters then you dont know much about how ice changes the airfoil shape and alters -increases- the stall performance of the wing. So that whole approach is not what IFR flying is all about: one of risk management, proper flight planning and good decision making skills. Not one where you need some grossly overpowered machine to get yourself out of places you don't belong in the first place. Perhaps you think that any flying above 4000 feet msl airport should only be allowed with aircraft with turbochargers as well.


Points don't get changed every annual and mags and plugs last more than 300 hrs. My Arrow's mags and plugs have almost 450 hrs on them, and previous sets have gone longer. You also say even the oil is inferior. Aviation oil, for piston engines, is designed differently than car oil. For one, car engines have tighter tolerances - because they run at more constant temps, because they are liquid cooled and thermostat controlled so they are machined closer - so the oil is different because air cooled aviation engines have much less tighter fits in pistons, rings, and cylinders to allow for a greater temperate swings, both in the engine and the operating environment. - and that poor thermodynamic efficiency is also what makes aviation engines have less efficient brake specific fuel consumption: pounds of fuel burned per horsepower per hour. (the smaller engine on Voyager was liquid cooled- that is the only way they could get the efficiency from it to do the around the world flight) The aviation oils also have different composition for corrosion control and oil contamination from the byproducts of combustion that gets into the oil. And when you say a car engine at highway speeds is working as hard as an airplane engine is a total joke. that is totally wrong, highway driving on a car engine is easy duty. Nothing comparied to my plane's, or any piston airplane engine, running 75% when in cruise.

Garrison is correct about props flexing.

Sport_Pilot

I never said anything about flying into convective weather. Actually I think no aircraft should be flown with less than 1500 FPM and must have an oxygen tank. This is to fly over much of the overcast weather, not through convective cells.

I should have said checked. Lasting 450 hours is unusual. 450 hours is nothing. If they lasted over 1000 as they do in a car, then they would be more reliable. This poor perfomance is due to the fuel, not the design of the plugs.

And you think its actually that save to fly such a loose and poorly cooled engine? There are air cooled automobile engines also. They have sense enough to put cooling fans on them. That means they can use detergent oil, so that the rings and valves do not stick in the sludge. Not fun to be on final and find out the engine is missing and you must make the landing. This I experianced and it was from stuck valves. Face it small airplanes are dangerous, and those arrogant enough to believe otherwise, should be damanding better performance from the industry.

Yes it is easy duty. Its the stop and start driving, and more often starts that isn't. Flying at 2500 RPM is the same duty as driving on the freeway. Look at your auto tach if you have one, it will do about the same, they the car can rev much higer and drive on the Autobaun screaming at 5000 or more and still be more reliable than an aircraft engine.