GA twins not certified for single engine flight?

[RotorAndWing]

It seems that whatever shop made up, tagged, and certified the hoses has some 'splaining to do.

Ya think?

 

[Henning]

It seems that whatever shop made up, tagged, and certified the hoses has some 'splaining to do.

It went there and further up the supply chain. I never got the full scoop, just that he found out they were part of a bigger shipment of counterfeit fittings. I doubt the shop that built the hoses were complicit in any wrong doing, but don't know for sure. I know I have to rely on the integrity of the supply chain to provide me genuine component parts when I build a hose. I just grab the parts, assemble, and pressure test. At that I have to assume I have a good assembly, I can't be sending every component out to be analyzed and confirmed, that's not realistic and is why we have the supply chain system we have.

 

[N801BH]

It went there and further up the supply chain. I never got the full scoop, just that he found out they were part of a bigger shipment of counterfeit fittings. I doubt the shop that built the hoses were complicit in any wrong doing, but don't know for sure. I know I have to rely on the integrity of the supply chain to provide me genuine component parts when I build a hose. I just grab the parts, assemble, and pressure test. At that I have to assume I have a good assembly, I can't be sending every component out to be analyzed and confirmed, that's not realistic and is why we have the supply chain system we have.

You got counterfeit parts. The SUPPLY CHAIN did not work.... Apparantly there was no traceability , which is required by the FAA..

Personally I am stunned the FAA didn't seize your failed parts and start an in depth investigation... Something does not add up here...

 

[Zeldman]

you have a serious misunderstanding of how both regulations and practical considerations are constructed. An engine failure is an emergency in virtually any airplane except maybe a B52

I had to break off an approach one time because ATC explained that there was a B-52 behind me on the dreaded 7 engine approach.

It really tickled me to listen as ATC questioned them. How many souls on board? 4. And which engine failed? #7. Fuel onboard? 7 hours.

What the....??? I had to go around because 1 out of 8 engines failed?

I only had one engine and it is night time and I was established on the localizer waiting for the glide slope to come up. 12.5% of their engines quit and it is an emergency. If my only engine quit I would have 100% engine loss but it was ok to have me go missed and try again at night.

Then again, they all had ejection seats and parachutes. I had.... uh...half a ham sandwich and a can of Pringles.

I digress... I was a civilian flying single engine IFR at night. I guess I was expendable...

 

[N801BH]

I had to break off an approach one time because ATC explained that there was a B-52 behind me on the dreaded 7 engine approach.

It really tickled me to listen as ATC questioned them. How many souls on board? 4. And which engine failed? #7. Fuel onboard? 7 hours.

What the....??? I had to go around because 1 out of 8 engines failed?

I only had one engine and it is night time and I was established on the localizer waiting for the glide slope to come up. 12.5% of their engines quit and it is an emergency. If my only engine quit I would have 100% engine loss but it was ok to have me go missed and try again at night.

Then again, they all had ejection seats and parachutes. I had.... uh...half a ham sandwich and a can of Pringles.

I digress... I was a civilian flying single engine IFR at night. I guess I was expendable...

Classic.... I LOVE it.........

 

[Computerjim]

Like I said, best thing you can do is more power. Dr. Bruce specifically operates his Seneca under gross to achieve the desired performance, and there's no reason why others can't do the same thing. If you have the plane because you need the useful load in it, then your safety margins are reduced.

I would love to put GTSIO-520s out of a 421 in the 310. At 375 HP a side, you'd have a power/weight ratio equal to a Commander 690, and suddenly you have great OEI performance. Of course, you also have to get the dead engine caged (there's a lot of drag on that prop), which is a consideration.

It's absolutely true that many twin pilots would be safer in a single. It's not just the plane, it is the pilot.

But, if you do the training, fly enough and keep your proficiency, there's a safety advantage.

That sounds great in theory, but them you would have to radically increase Vmc or the size of the rudder to stay upright on one engine. There is no free lunch.

 

[Ted]

That sounds great in theory, but them you would have to radically increase Vmc or the size of the rudder to stay upright on one engine. There is no free lunch.

I didn't say it was easily doable or without other engineering questions. Remember, we're in the design phase here.

 

[Ted]

They are trainers though, they have their limitations. They do a good job of teaching people why you don't want to overload a twin on a hot day...

Piston twins are not all trainers. All of them have their capabilities and limitations.

 

[Henning]

You got counterfeit parts. The SUPPLY CHAIN did not work.... Apparantly there was no traceability , which is required by the FAA..

Personally I am stunned the FAA didn't seize your failed parts and start an in depth investigation... Something does not add up here...

They did get the parts and they did trace the parts back, the investigation at that point was already in process.

 

[poadeleted20]

I had to break off an approach one time because ATC explained that there was a B-52 behind me on the dreaded 7 engine approach.

I few years back when I was in the USAF I read a B-52 incident report the last line of which was, "An uneventful 3-engine-out landing ensued."

BTW, when you look at the 4-cylinder 2x150-200HP twins like the Apache, Seminole, Cougar, Duchess, etc., realize that they have two engines not for performance, but for training. You could get the same performance they offer in a single with one big engine. However, the flight schools want to control costs, so they wanted twins with the smallest engines feasible, and the manufacturers produced them for that market niche even though they offer little practical advantage over a single in the same performance range to justify their greater costs.

 

[EdFred]

I had to break off an approach one time because ATC explained that there was a B-52 behind me on the dreaded 7 engine approach.

It really tickled me to listen as ATC questioned them. How many souls on board? 4. And which engine failed? #7. Fuel onboard? 7 hours.

What the....??? I had to go around because 1 out of 8 engines failed?

I only had one engine and it is night time and I was established on the localizer waiting for the glide slope to come up. 12.5% of their engines quit and it is an emergency. If my only engine quit I would have 100% engine loss but it was ok to have me go missed and try again at night.

Then again, they all had ejection seats and parachutes. I had.... uh...half a ham sandwich and a can of Pringles.

I digress... I was a civilian flying single engine IFR at night. I guess I was expendable...

My engine would have started running a teensy bit rough at that point.

 

[N801BH]

They did get the parts and they did trace the parts back, the investigation at that point was already in process.

Ya got a date on when this happened ??

I would like to browse the internet to how how the FAA addressed, fined or jailed the vendor /supplier/ manufacturer...

Thanks in advance...

 

[Henning]

Ya got a date on when this happened ??

I would like to browse the internet to how how the FAA addressed, fined or jailed the vendor /supplier/ manufacturer...

Thanks in advance...

1990 I would have bought my Travelair, this was out of Long Beach. Oh, do some research in the whole subject, they had big issues at the time. What happened as far as arrests? Likely nothing, the problem roots in China.

 

[bobmrg]

Thanks for the responses, i ask this question simply because i do not know much about multi aircraft. I was just curious the differences as to why commercial multi's can climb safely with an engine out vs the comparison. I probably overstepped my bounds by asking this and assuming, i just dont know much about them like i say. Thanks for the insight!

...but the title of the thread implies there is no regulation...post #20 refutes that.

Bob Gardner

 

[Dead Stick]

...but the title of the thread implies there is no regulation...post #20 refutes that.

Bob Gardner

When it comes to OEI performance, there are definite certification requirements that must be met. It's just that they are not very demanding and most people think twins are capable of performing at much higher levels on one engine. Silly people. But, if flown properly, it is enough.

 

[Ted]

When it comes to OEI performance, there are definite certification requirements that must be met. It's just that they are not very demanding and most people think twins are capable of performing at much higher levels on one engine. Silly people. But, if flown properly, it is enough.

Correct. And also depending on weight. Most often, they're flown heavy, though, which hurts.

 

[Henning]

Correct. And also depending on weight. Most often, they're flown heavy, though, which hurts.

That was one thing Betty Faux taught me about on my ME Checkride in my Travelair. She stressed that fuel management was different in a twin because tankering excess fuel costs SE performance and with low power twins it adds some extra steps to your fuel planning, and a good part of the oral revolved around that.

 

[Dead Stick]

Correct. And also depending on weight. Most often, they're flown heavy, though, which hurts.

When it comes to OEI performance and safety it all boils down to three things:

#1. Available Horse Power. Single-engine performance in nearly all piston-powered light twins is abysmal. They have two engines because they need two engines. Loss of power is the primary culprit. Remember, normally aspirated aircraft lose power with altitude. An aircraft's climb ability is directly proportional to the amount of "excess" power that it has available vs. what is needed to maintain level flight. For example, if a 200 HP normally aspirated airplane requires 100 HP to maintain level flight it would (at SL, ISA day) have 100 "excess" HP to use for climb. At 10,000' MSL, the engine might only be able to produce 130 HP, leaving it with a 30 HP surplus. This is also why light twins typically perform so poorly on one engine. Take, as an example, a twin Comanche with two 160 HP engines. If that airplane required, say, 150 HP to maintain level flight it would have 170 "excess" HP to climb with. If it lost an engine, it would have lost 50% of its available power, but with just 10 "excess" HP, it may have lost 95% of its ability to climb. This, of course, will also apply to all other light twins and is the reason why turbocharged aircraft perform so well - you would be able to maintain SL power up until you reached the "critical altitude" for the particular engine. In some cases, this can be as high as 18,000' MSL.

#2 Weight. That's the key to the safe operation of ANY propellor driven piston or turboprop twin light aircraft. Airplanes have better performance when they're not flown at maximum allowable weights. It's that simple. It's too bad that many (most?) twin pilots don't seem to understand or care about this. It takes real discipline to operate these aircraft in a manor that will insure safety. The aircraft manufacturers don't help much either. About the most information they give you on piston twins are the almost universally ignored accelerate/stop charts - after all, they're so restrictive. And whenever a manufacturer or modifier comes up with something that does enhance single engine performance, hence increases safety (ie VGs, increased HP mods like Ram conversions, etc) they almost always seem to up the allowable gross weight just enough to bring the performance back down to barely enough to meet certification requirements. The result is that, in spite of having installed all of the available mods to enhance safety, pilots end up adding payload to the aircraft which once again means that they end up flying airplanes that will meet - but just barely - the certification minimum requirements and that's if they happen to pay attention to the weight and balance and other limits. If you want to understand how to safely operate a light twin just do a search on what Dr. Bruce has posted on the subject. I'd ride with him in his Seneca any day. I'd let my family ride with him too.

#3 Training. Let's be honest, a one hour flight review every couple of years isn't going to cut it for most guys. Even if you have flown your light twin every day for the past ten years and logged 500 hours+ per year it wouldn't make one bit of difference. Sitting in the left front seat with the autopilot on droning on from point A to point B then on to point C,D... does ABSOLUTELY nothing for you when it comes time to deal with an actual OEI emergency in a light twin. What matters at that point in time is what training you've done recently. Using a BFR as an excuse to get a new rating or endorsement is a good thing, but common sense dictates that if you're flying something serious such as a light twin on a regular basis, then that's where your exposure is and that's where you'd better be sharp when it comes to stuff like OEI procedures. There may be legitimate ways to legally go two or more years between serious recurrent training sessions in your light twin, but I've never met anyone yet that can go that long and still be as sharp as they should be. In fact, most twin drivers I know could use far more training in their airplane, not less - like every 6 months. You must never equate currency with proficiency.

 

[Ted]

You said what I've already said, you just used more words.

 

[coloradobluesky]

Engine outs do occur. Although they are rare. I read that Cirrus has yet to have a crash because of an engine malfunction. That was as of 2012, not sure if its still true. Shows you the reliability of first run engines.

Just don't run out of fuel, and be willing to put up in a motel somewhere while the storm passes and you will probably make it. Oh, and be a really attentive, good pilot. Fly the plane intensely and with concentration. Be able to handle 30knots of crosswind, stuff like that.....

 

[Henning]

You said what I've already said, you just used more words.

 

[bobmrg]

Correct. And also depending on weight. Most often, they're flown heavy, though, which hurts.

Richard L. Taylor, who has written a book or two on aviation subjects, once told me that he would not fly a light twin if it was loaded within 400 pounds of max gross.

Bob Gardner

 

[Ted]

Richard L. Taylor, who has written a book or two on aviation subjects, once told me that he would not fly a light twin if it was loaded within 400 pounds of max gross.

Bob Gardner

Reasonable generalization. Depends on the plane, of course. Take the 310 I fly. With 300 HP Colemill engines, the power to weight ratio at gross is better than a stock 310 at 400 under.

Of course, take the plane I fly, put it 400 under, even better.

 

[Henning]

Richard L. Taylor, who has written a book or two on aviation subjects, once told me that he would not fly a light twin if it was loaded within 400 pounds of max gross.

Bob Gardner

I share his feelings.

 

[Henning]

Reasonable generalization. Depends on the plane, of course. Take the 310 I fly. With 300 HP Colemill engines, the power to weight ratio at gross is better than a stock 310 at 400 under.

Of course, take the plane I fly, put it 400 under, even better.

Yep, that's why the horsepower increase conversions are so popular on light twins, they add significant single engine capability because the increase in excess horsepower converts to climb ability very efficiently, just adding 10hp a side changes things dramatically in ability at Vyse.

Horsepower and weight both buy the same thing, if you can afford to work from both sides of the equation, so much the better.

 

[Ted]

I've been doing both. Already got the Colemill, and the plane is over 50 lbs lighter than when I started flying it. Got more weight reduction in mind, too. A few extra power mods on the list, but those are harder.

 

[bburnett]

I have been flying a turbo Twin Comanche for 2 years now. Turbo normalized, Miller conversion (IO360C1C, 200 hp. each side) Robertson STOL. It will climb almost as good as a 172 on 1 engine.

Single engine service ceiling is +18,000.

She's fat but fun.

 

[ronnieh]

One of the problems with the training is "how to train". How do you practice those things that are just too dangerous to do in a plane? I wrote in another thread that there is approximately 100 seconds in each flight in most light twins that one may just have to accept that loss of an engine most likely will not turn out well. All the rest of the flight segments can and should be practiced on a regular basis. IFR pilots need to be very proficient on one engine out procedures.
Back to the OP, I think you question has been answered quite well by several.

 

[Ted]

That is the problem. The sims don't fly like the plane, the plane it's too dangerous. At some point, you just have to accept the risk that something may go wrong that you can't handle.

Autofeather would sure help.

 

[Henning]

I've been doing both. Already got the Colemill, and the plane is over 50 lbs lighter than when I started flying it. Got more weight reduction in mind, too. A few extra power mods on the list, but those are harder.

One thing I wanted to do with my 310 was build a water jacket heat exchanger for the exhaust pipe, replace the combustion heater with an insulated tank for anti freeze, and plumb it all together with a heater core/blower box in the cabin. The augmentor boxes on the D would have made it simple. Man, I would look out at the nacelles on a cold night and see the glowing behind the lovers and think, "Man, I need that heat in here!" I think that would make a successful STC, I don't know one twin owner who wouldn't trade 100lbs, if that, to get rid of their combustion heater.

 

[ronnieh]

+1000. I hate those combustion heaters!

Yep, Ted sometimes stuff happens. It would not be technically difficult to build realistic FTD's for the light twins. It would never be economically feasible. Very few pilots are going to fork out $3K-$4K even once a year for training. The insurance underwriters have been largely responsible for the acceptance of sim training in the turbo prop market. It just is what it is.

 

[dans2992]

Is it really that hard to duct the heat from a wing-mounted engine into the cabin?

I guess it is, but I still remain unconvinced...

 

[Henning]

Is it really that hard to duct the heat from a wing-mounted engine into the cabin?

I guess it is, but I still remain unconvinced...

It's not getting it into the cabin, it's that it loses all it's heat by the time it gets there.

 

[Dav8or]

And here is the answer to all this twin with an engine out nonsense-

The amazing Boomerang

According to Tres Clements, the custodian and pilot of this plane now, the engine out drill for either, take off, cruise or landing is best preformed with both feet planted firmly on the floor. All you do is a pitch adjustment. Vmc roll over is impossible in this plane.

Performance specs for the Boomerang-

• 75% cruise @ 22,000 ft = 264 kts for 1500 miles.
• 50% cruise @ 24,000 ft = 210 kts for 2100 miles.
• Max range = 37% cruise @ 20,000 ft, 186kts for 2960 miles.
• 171 gallons of gas
• 1000 lb cabin payload
• 865 lbs payload with full fuel
• 73-88 kt stall
• 5 seats

Sadly, I think people just can't get over the way the world's safest twin looks and so there is just one in existence. Burt Rutan says that of all the planes he has designed, this is the only one that he wishes would be put into production.

 

[flyingcheesehead]

Thanks for the responses, i ask this question simply because i do not know much about multi aircraft. I was just curious the differences as to why commercial multi's can climb safely with an engine out vs the comparison. I probably overstepped my bounds by asking this and assuming, i just dont know much about them like i say. Thanks for the insight!

Not at all, it was a good question, thanks for asking it! That's what we're here for...

Good answers, just to clarify, i did not post this thread to try and start arguments or say anything bad about multi's or anything. I just heard about this and wanted to post on here to get some insight about this topic. I just wanted to know what the differences were between the two and why they perform differently given the situation. Thank you for your replies!

But there's this dead horse here! We need to beat it for a while!

Many threads on PoA develop a life of their own that lasts long after the original question was answered... It's entertaining if nothing else!

 

[flyingcheesehead]

And here is the answer to all this twin with an engine out nonsense-

According to Tres Clements, the custodian and pilot of this plane now, the engine out drill for either, take off, cruise or landing is best preformed with both feet planted firmly on the floor. All you do is a pitch adjustment. Vmc roll over is impossible in this plane.

Performance specs for the Boomerang-

• 75% cruise @ 22,000 ft = 264 kts for 1500 miles.
• 50% cruise @ 24,000 ft = 210 kts for 2100 miles.
• Max range = 37% cruise @ 20,000 ft, 186kts for 2960 miles.
• 171 gallons of gas
• 1000 lb cabin payload
• 865 lbs payload with full fuel
• 73-88 kt stall
• 5 seats

Sadly, I think people just can't get over the way the world's safest twin looks and so there is just one in existence. Burt Rutan says that of all the planes he has designed, this is the only one that he wishes would be put into production.

I do too! I love the Boomerang. It's an amazing airplane, and really shows what a genius Burt Rutan is. Can you believe that his starting point for that design was the Baron? He took all the non-ideal characteristics, and instead of trying to compensate for them, simply added MORE non-ideal characteristics to cancel them out, and the Boomerang was the result. True genius. I'd love to have one.

You forgot to mention above, it performs like that on a total of 410hp - Less than a Seneca III-V, Baron, etc that are quite a bit slower too.

 

[Henning]

And here is the answer to all this twin with an engine out nonsense-

The amazing Boomerang

According to Tres Clements, the custodian and pilot of this plane now, the engine out drill for either, take off, cruise or landing is best preformed with both feet planted firmly on the floor. All you do is a pitch adjustment. Vmc roll over is impossible in this plane.

Performance specs for the Boomerang-

• 75% cruise @ 22,000 ft = 264 kts for 1500 miles.
• 50% cruise @ 24,000 ft = 210 kts for 2100 miles.
• Max range = 37% cruise @ 20,000 ft, 186kts for 2960 miles.
• 171 gallons of gas
• 1000 lb cabin payload
• 865 lbs payload with full fuel
• 73-88 kt stall
• 5 seats

Sadly, I think people just can't get over the way the world's safest twin looks and so there is just one in existence. Burt Rutan says that of all the planes he has designed, this is the only one that he wishes would be put into production.

I think the Boomerang is a just fine plane and he should have seen it through to production. The competing market is priced around a mill and a half for a new G-58 Baron. Is the Boomerang pressurized? That would give him the market. I don't believe the plane failed on looks, I think the plane failed on lack of effort to bring it to market. If he could have brought an unpressurized one to market for $750k and a pressurized one for $1.2MM, powered by a pair of Diesels, I bet he would have a market.

It seems efficient enough, and it comes with two tubes, I wonder how it would scale up to airline service?

 

[flyingcheesehead]

I think the Boomerang is a just fine plane and he should have seen it through to production. The competing market is priced around a mill and a half for a new G-58 Baron. Is the Boomerang pressurized? That would give him the market. I don't believe the plane failed on looks, I think the plane failed on lack of effort to bring it to market. If he could have brought an unpressurized one to market for $750k and a pressurized one for $1.2MM, powered by a pair of Diesels, I bet he would have a market.

Yes, it's pressurized.

 

[N801BH]

Yes, it's pressurized.

Yup.... The round windows are the givaway...

 

[Dav8or]

I do too! I love the Boomerang. It's an amazing airplane, and really shows what a genius Burt Rutan is. Can you believe that his starting point for that design was the Baron? He took all the non-ideal characteristics, and instead of trying to compensate for them, simply added MORE non-ideal characteristics to cancel them out, and the Boomerang was the result. True genius. I'd love to have one.

You forgot to mention above, it performs like that on a total of 410hp - Less than a Seneca III-V, Baron, etc that are quite a bit slower too.

Yep, 20 gph total. Less if you go LOP.