Aircraft Loses Engine Veers Off Runway

[punkalouver]

Almost looks like he put a lot of reverse thrust on the good engine a little too early when the weight was not fully on the ground.

Video Here......


MSN

[Less Hair]

Isn't that their factory new one only delivered very recently?
No, it is not the Bangladesh one. Good to see everybody okay.

[340drvr]

Interesting to watch. It looks like the plane even touched down at an angle. As punkalouver suggests, maybe inappropriate use of reverse, or, perhaps they had the rudder trimmed way over for one-engine flight, and had no room for pedal travel to straighten out? (just a total guess). Yes, glad no one was hurt, it could have been much worse.

[Pilot DAR]

or, perhaps they had the rudder trimmed way over for one-engine flight, and had no room for pedal travel to straighten out?

'Not what I'm thinking... There would not be enough rudder trim travel available to overcome the ability to simply use the pedals to maintain directional control.

I opine that, as mentioned, the inappropriate use of reverse on one engine was the prime factor, perhaps associated with what appears a rather fast touchdown. Stressed pilot due to the already failed engine?

[Jhieminga]

Perhaps the pilot had an issue with the meteo report for that particular airport? He successfully took out the measurement station....

[First_Principal]

Whatever the initial cause the aircraft's angular momentum was soon greater than the machine control and/or pilot's ability to counteract.

I had this happen to me once, in a tail-dragger. It was a nice day but with reasonable cross-wind, I came in a little faster than normal and upon landing the a/c wanted to go left, nothing I could do would stop that (this a/c has notoriously poor brakes) so left we went. Fortunately for my ego I was not going too fast, nor the turn too sharp, so it ended up being a nicely proscribed turn into a not inappropriate area, and I don't think anyone was watching anyway. However that I clearly remember it to this day is testament to the significance of the moment.

In my case I'm reasonable sure there was nothing other than insufficient ability of the controls (wheel brakes and rudder - it was a castoring tail wheel) to cope with the angular momentum of the machine. What I see in this video appears similar to my experience - although it's possible there could be an issue with the pilot's knowledge/ability around opposite lock correction and/or momentum, which could have an effect.

With regard to the latter, I wonder if there's a place to learn a little about this during training? In my case the knowledge had been learned during a misspent youth with lots of cars/motorbikes coupled with mud or gravel, however there will be people who've never had the experience and may simply not know how to cope, and foot control is somewhat different than wheel anyway...

FP.

[Peter Fanelli]

Kudos for getting it nicely parked in the box.

And since he cleared the runway operations can continue?

[Pilot DAR]

Whatever the initial cause the aircraft's angular momentum was soon greater than the machine control and/or pilot's ability to counteract.

Well.... yes.... eventually during the event, but.... The tricycle is naturally directionally stable on the runway (unlike a taildragger, which would surly behave this way once initiated). Once the destabilizing force was removed (asymmetry reverse, I opine), the plane would have naturally aligned itself to it's path (the runway centerline hopefully). But, yes, you can get to a point where that won't work anymore, and this pilot did.

This would be similar to landing with a flat tire, controllable, but you have to!

[Procrastinus]

Would one ever use reverse thrust on live engine during an asymmetric landing? Surely that would produce an uncontrollable yaw?

[meleagertoo]

Apparently two or three people/bystanders at the runway's edge had a falrly close shave too!

[Pilot DAR]

Would one ever use reverse thrust on live engine during an asymmetric landing? Surely that would produce an uncontrollable yaw?

I did once, but very, very carefully. 'Turned out it worked fine, but we were uncertain, so very cautious. We were doing a single engine landing in a Piper Cheyenne II, into a relatively short, snow covered runway, so "guarded" use of reverse was considered a balance of assuring a safe stop.

[what next]

Originally Posted by Procrastinus

Would one ever use reverse thrust on live engine during an asymmetric landing? Surely that would produce an uncontrollable yaw?

Not if you do it the same way as you are supposed to in every landing: Once the wheels are on the ground apply brakes and check for braking action and directional control. Only apply reverse thrust when you get both. Depending on aircraft type and runway conditions, reverse thrust creates between 10 and 30% of the braking force of the wheel brakes and should therefore easily be controllable even in an asymmetric condition.

[Pilot DAR]

Depending on aircraft type and runway conditions, reverse thrust creates between 10 and 30% of the braking force of the wheel brakes and should therefore easily be controllable even in an asymmetric condition.

Well.... depending upon airplane type... My experience with asymmetric reverse at runway speeds is limited to the Cheyenne and Twin Otter. For both those planes, lots of reverse would equate to more than 10 to 30% of braking, but more importantly, for the Twin Otter, and other types, the engine is further outboard than the wheel, greater arm for reverse thrust than braking. And, if you apply maximum braking, either sliding a tire, or antiskid will limit braking effect, where you keep getting the reverse effect.

A pilot must be very cautious with asymmetric reverse, until they know the plane well, do not assume that you'll have enough directional control to overcome the asymmetry you could create for yourself!

[mustafagander]

As I recall it, asymmetric reverse is SOP on B767. I think there is a caution in the FCTM to the effect be careful.

[what next]

Originally Posted by Pilot DAR

A pilot must be very cautious with asymmetric reverse...

To add some spice to this discussion I looked up the "SINGLE ENGINE APPROACH, LANDING AND GO-AROUND" checklist (capitalisation as per POH) in the Pilot's Operating Handbook of a Dornier 228-100 from 15 November 1983. The aircraft involved in this accident is not a "-100" variant so possibly there will be some differences.

It says on page 3-26-3:

LANDING
Use normal landing procedures.
After touchdown, retard the POWER lever of the running engine progressively between FI and REVERSE to avoid excessive thrust or reverse drag on this engine. Consider longer landing distance and landing roll.

CAUTION
Before retarding the POWER lever into REVERSE, be sure to have the nose wheel on the ground.

Use the brakes for deceleration and the NWS for directional control.

Myself I have not flown the Do228 but briefly the Sa228 (Metro). It has the same engines and the operating procedures are similar. Using reverse thrust in case of a single engine landing was not forbidden or discouraged on this type either.

Edit: One general consideration for this kind of emergency landing. In the event of a single engine landing it will be very difficult to find the zero-thrust setting on the remaining engine. If that exists at all (unless the engine is shut down). So there will always be some thrust remaining and thus an asymmetry that needs to be balanced with steering and differential braking. No what's better: Having that remaing thrust aid the braking action or work against the brakes? There can be only one answer.

[punkalouver]

A long time ago, I scared myself in a Mooney. I had been checked out recently on it and wanted to stay current. One should keep in mind that a Mooney is the kind of plane that really floats on landing if the airspeed is just a few knots above the proper approach speed. Anyways, I did not mark down a bunch of quick reference notes(like I now do on the various aircraft I fly, which allows me to reference them and feel reasonably comfortable in flying a particular aircraft after a while).

I arrived at the airport with some knowledge having evaporated. One item was the rotation speed. No problem, I will just look it up in the POH. Unfortunately, it was not in the aircraft, as legally required for a flight. The office where this POH might be was closed. I decided to fly anyways. I would simply just rotate at an airspeed about ten knots faster than what I was guessing was the recommended rotation speed. There was a 15 knot crosswind and I got a huge surprise on the takeoff roll when the aircraft got light on its wheels and quickly went toward the side of the 100' wide runway(although remaining parallel to the centerline). I quickly pulled back, got airborne and learned the lesson of being on the ground but having minimal friction due to having plenty of lift.

I suspect that this could be applicable in this incident. The aircraft appears to float for a while suggesting excess airspeed. There is a break in the video but it does appear that the aircraft is light on its wheels as it veers to the right. The investigators may be looking into a possible situation where significant reverse was selected when there was minimal friction to prevent a lateral excursion. Perhaps, being light on the wheels is not much different than being on a slippery runway. Therefore, it is suggested to ensure the aircraft is firmly on a dry, paved runway prior to applying asymmetric reverse.

[Tarq57]

Not much, if any indication that any left rudder was applied during that rollout.

[TowerDog]

Indian CG Dornier 228 off the runway

Left engine failed before landing..

You Tube

[pattern_is_full]

Hmmm - a case of selecting reverse pitch out of habit, with one engine inop? Often a recipe for a bad day.