what if one engine fails on twin engined piston aircraft

[imcool]

I am wondering, if an aircraft can still fly/reach nearest airport/land in case of one engine failure on a small twin engine piston aircraft with no more than 3-4 people on board. What are chances of survivals? for example - Beechcraft Baron series aircrafts.

I googled and found articles only about Multi Jet Engine planes, that they can fly with one engine and land but not much about twin engined piston aircrafts.


Thanks for reading

[ahramin]

Depends on the plane and the conditions and the weight and balance. Last time I checked a Baron it could hold 5000' at max weight in isa conditions.

[PilotDAR]

A part of the prevailing requirement applicable to most light twin engined aircraft reads:

Sec. 23.67

Climb: One engine inoperative.

(a) For normal, utility, and acrobatic category reciprocating engine-powered airplanes of 6,000 pounds or less maximum weight, the following apply:

(1) Except for those airplanes that meet the requirements prescribed in Sec. 23.562(d), each airplane with a of more than 61 knots must be able to maintain a steady climb gradient of at least 1.5 percent at a pressure altitude of 5,000 feet with the--

(i) Critical engine inoperative and its propeller in the minimum drag position;

(ii) Remaining engine(s) at not more than maximum continuous power;

(iii) Landing gear retracted;

(iv) Wing flaps retracted; and

(v) Climb speed not less than 1.2 .

There are variations of this, depending upon some design factors.

[goingnowherefast]

Most modern and well maintained piston twins will maintain some reasonable altitude on one engine.

A clapped out, tired and overloaded twin probably won't maintain altitude. Nice, clean, properly maintained, and legally loaded twin should be able to maintain something around 3000-7000' asl, depending on model, load and temperature.

[telex]

[kevind]

The old pilots proverb, the 2nd engine takes you the scene of the accident.

[PilotDAR]

the 2nd engine takes you the scene of the accident.

A very good reason to get better at landings!

[DCL415]

I got my multi rating this summer and in a very hot day, the piper seminole (PA-44-180)was able to climb single engine (dead engine at zero thrust) at 150fpm at 5000 feet indicate with 3 people on board and 65 gallon of fuel, the calculate single engine service ceiling (climb drops to 50fpm) was aprox at 5900 feet.

[Victory]

"Zero thrust" settings are usually a bit liberal since the instructor or check pilot doesn't want to die.

[goingnowherefast]

To further your findings about twin jet aircraft. The vast majority will be able to continue takeoff past a certain point (called V1) if an engine were to fail.

In the simplest of terms, a plane with more than 9 passenger seats is required to either abort the takeoff and stop on the remaining runway, or to continue the take-off and climb safely with an engine failed.

Small twins have a different requirement as posted above by PilotDAR. I really doubt most small twins could continue flying away from the runway if an engine failed at, or shortly after rotation. Especially with the gear down, take-off flap and propeller not yet feathered. That's why most commuter and transport category propellor aircraft have tons of power and propellor drag reduction features such as auto-feather.

[the-minister31]

The theoretical answer is yes. Twins are designed to fly on one engine with a service ceiling of about 5-6000 feet, given you clean the aircraft and feather the affected engine.

From my experience, my answer is the famous "it depends"... It really does, a lot. Temperature, weight, CG, config, speed at which you lose the engine, etc. Needless to say, aircraft that have a lot of power like the Navajo of the Aztec will fly better on one engine then something like a Twin Comanche, which doesn't have a lot of power to begin with. Sometimes the aircraft won't climb much, or at all. If you are above max gross, the CG is too far forward or OAT is high, it maybe won't even maintain altitude !

Now, my story... The aircraft was at about 90% gross weight, with a forward CG at about ISA temp at 1000 ASL at climb speed, which corresponded to blue line. By the time I identified, verified and feathered the affected engine I was down to 500 even if I was right on blue line the whole time... Only with bit of flaps to lower the nose and the downed engine feathered I was able to maintain altitude. I found out light piston twins can be really surprising when one engine fails. Don't get yourself into trouble flying too slow or too low !

[DCL415]

"Zero thrust" settings are usually a bit liberal since the instructor or check pilot doesn't want to die.

Also flight schools want to reduce wear and tear of the engine by not feathering and restarting twice or more per training flight

[goingnowherefast]

Then there's always the risk of the engine not un-feathering or failing to restart.

It used to be a requirement to shut off an engine during initial multi training. Apparently enough single engine landings from failed restart attempts changed that requirement.

[Trevor]

I am wondering, if an aircraft can still fly/reach nearest airport/land in case of one engine failure on a small twin engine piston aircraft with no more than 3-4 people on board. What are chances of survivals? for example - Beechcraft Baron series aircrafts.

I googled and found articles only about Multi Jet Engine planes, that they can fly with one engine and land but not much about twin engined piston aircrafts.

Thanks for reading

As others have indicated, there are a lot of variables at play in your question. In short, yes, light twins are designed to maintain altitude with one engine shutdown and the propeller feathered. Sometimes reaching this point requires a gradual single-engine let down to the single-engine service ceiling, which is in the 3,000-7,000’ ASL range for most light piston twins. I noticed Telex posted the single-engine service ceiling information for the Baron. Remember, like all charts in the POH, those were created by skilled test pilots flying new airplanes, with new engines and new propellers. Expect to see lower numbers in the real world.

In a single-engine anything, engine failure immediately sets you down one path – a forced landing. You establish a glide, search for a correctable cause of failure, and do your best to find a safe landing site.

A twin gives you choices – choices that sometimes need to be made very rapidly. An engine failure immediately after takeoff must be handled differently from one at altitude. You’re low, slow, and possibly still have the gear down causing loads of drag. You might only have a few seconds to realize the failure and pilot the airplane to the ground before losing airspeed and control. In that situation, there’s no chance of running the IDENTIFY-VERIFY-CAUSE-CORRECT checklist.

In my twin, the ‘danger zone’ is about 10 or 15 seconds after liftoff when I’m too low, too slow, and too draggy to do anything but crash. For me, I brief myself that below 105 mph (single-engine climb speed) and 500’ AGL, my plan is to kill both engines and crash straight ahead. I need 105 mph to continue flying and avoid hitting the ground, or I need 500’ to drop the nose and gain the airspeed. If I try to fly out of this ‘danger zone’ with a failed engine, odds are, I’ll end up rolling over and splatter myself along the departure path. I flew a UC-1 Twin Bee a couple years ago, and with all its drag I figured I had the glide-ratio of a ton of bricks should the engine(s) fail. Sadly, an accident in February 2019 proved this correct – engine failure at 200-300’ AGL (http://www.kathrynsreport.com/2019/02/s ... ident.html).

Failure at altitude gives you time, time to realize the failure, to run through the checklist, and because you already have altitude and airspeed, it’s more likely you’ll maintain control. Even if your airplane will not maintain altitude, the rate of descent with one engine operative will certainly extend your ‘glide’ and afford you more time to find or reach a safe landing site than you would in a single-engine failure.

Learning to fly multi-engine airplanes is about dealing with failures and choosing solutions that will result in positive outcomes (i.e.: you live). With both engines running smoothly there’s really no difference between flying a single and twin-engine airplane.

[Schooner69A]

As noted above: the thing about many light twins like the Baron is that the conditions associated with the single-engine climb chart require:


(iii) Landing gear retracted;

(iv) Wing flaps retracted; (or in most favourable position)


There is no guarantee that any of these aircraft will climb until those items have been actioned.

Until so, you may have a vertical velocity, but it could very well be negative...

[imcool]

Thanks a lot for all valuable inputs, I am overwhelmed by your replies. Very informative.
If i understood correctly, a twin engine piston aircraft can land with fair chances of survival provided many conditions discussed above.

[Zaibatsu]

"Zero thrust" settings are usually a bit liberal since the instructor or check pilot doesn't want to die.

Have you ever flown a multi engine aircraft?

A simulated engine failure is NEGATIVE thrust. With everything hanging out in some circumstances. It’s only after they’ve accelerated to blue line, cleaned up the aircraft, and pretended to secure the engine that it goes UP to zero thrust.

If there’s a monkey at the controls and airspeed is decreasing or yaw not being controlled there’s another set of controls and a throttle connected to a perfectly functioning engine right there.

And because we are doing this at altitude and not actually on rotation or just airborne the risk is downright minimal.

Setting a couple extra inches or a couple hundred pounds of torque will mean jack if they jam the throttle in on a go around with no rudder.

A bit liberal. What will they think of next?

[Capt. Underpants]

Then there's always the risk of the engine not un-feathering or failing to restart.

It used to be a requirement to shut off an engine during initial multi training. Apparently enough single engine landings from failed restart attempts changed that requirement.

TC changed that requirement after the crash of a TC Twin Otter near Hamilton, ON in the late 70's / early 80's. Three inspectors were out on a recurrent training flight and while I don't remember the exact circumstances, I recall hearing that the "good" engine was seriously over-torqued and failed during a simulated go around. An inability to restart the other one led to a dead stick landing that went horribly wrong and cost two inspectors their lives.

Oh, and sorry for picking nits, but to the OP, the plural of "aircraft" is still "aircraft". No "s". Common error.