jet/bird evasive action

[sevenstrokeroll]

I haven't seen a good discussion on evading bird strikes, especially sucking birds into engines.

I learned to fly at a very ''birdy'' area on the bay of san francisco some 36 years ago. What I learned there wasn't in books.

I offer this:

if you are head on with a formation of birds, bank YOUR plane about 60 degrees, this takes the engines (assuming underwing engines like a 737) out of the plane of the formation of birds...thus saving your engines.

if you are on approach, birds usually dive, so climb.

it is an old wives tale, but if birds are on the runway, you might flip on your wx radar...I've seen flocks of birds takeoff the instant the radar has been turned on.

provide ''bird'' reports to atc for general dissemination.

watch out for birds just above an overcast as you pop out on climb, or just below the undercast as you pop out below!

good luck

[Machinbird]

To add to sevenstroke's excellent points:
For a jet aircraft, there is a tiny spot in the middle of your windscreen that all relevant birds are going to appear out of. Figure out where your spot is and give that spot extra attention while in high probability bird territory. By the time you see birds using an aircraft detection and avoidance type scan, it is probably too late to influence the outcome.

And if you see the specks in the distance, you don't need to ID them before taking avoidance.:}

[aviatorhi]

Unless you have JT8Ds slung on your airplane, then you can plow through anything. :ok:

[Old Fella]

Aviatorhi This may change your mind.




File:JT8D Engine after Bird Strike.jpg - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/File:JT8D_Engine_after_Bird_Strike.jpg)

[aviatorhi]

I've seen tons of pictures of JT8s after bird strikes and that's not the worst of it, I've been ondboard when weve plowed through them as well, in no instance has an engine stopped running.

[sevenstrokeroll]

and a JT8D on the back, like a DC9 is even better! :-)

excellent point about the ''spot" on the windshield...good job Machinbird...RU near chicago?

[aviatorhi]

727 in my case, but yes, same concept.

In my experience birds usually show up at times when there are more pressing issues to worry about. I remember one showing up right after Vr (before V2) and in situations like that all you can (and should) really do is fly the plane and not even worry about "evading" the thing, too low on airspeed, too close to the ground etc. etc. to be doing unplanned maneuvers. Once you're up and off it's up to the pilot (captain) what they want to do. I've seen people try to evade the big ones only hit them anyway (Abatross) while the small ones hit before you can react (Swallows, with or without coconuts).

[sevenstrokeroll]

fine points...especially about swallows with cocoanuts.

you do what you can...I was thinking of the sully flight...if he was flying a dc9 or 727 he would have been on time to charlotte. also using the bank technique might have kept one of the engines out of the bird zone

but if you are at V1...its a tough place to be

[sevenstrokeroll]

thanks everyone for your great points.

I just wish someone ''in charge'' would actually look into evasive action techniques for jet airliners. Seems a shame we really don't know too much more than we did before sully's landing.

but if you have a flock of birds in your window...try the bank!

[Centaurus]

Flocks of birds seen on the runway can be lethal and the decision to abort or press on becomes a critical choice. Well below V1 is not a problem but depending on surface conditions and length of runway an abort can produce it's own hazards especially in jet aircraft.
In another life I lined up at Edinburgh RAAF, South Australia, runway. It was a long runway and there had been recent heavy rain which had cleared. I was flying a RAAF Viscount. We could see flocks of sea gulls on the runway pecking away at thousands of what seemed to be tiny worms.

We asked ATC to have the duty fire tender to squirt water at the sea gulls (after all that is how rioting crowds in some countries are dispersed). The sea gulls didn't like this too much and flocked off.

Shortly before V1 we observed a mass of sea gulls getting airborne from the grass adjoining the runway and it was clear we were going to run into them as they flew across the runway at cockpit height. We aborted the take off at the same time we felt numerous bird strikes and due to the long runway we stayed off the brakes and coasted to stop using the full length. We saw no point in risking hot brakes when excess runway was available. The ground fine position of the props was very effective at high speed.

There was hardly any damage to the aircraft despite about 25 dead seagulls being found by the fire tender crew.

[sevenstrokeroll]

centaurus...good story...good decision. wise use of flat pitch instead of wheel brakes.

[TAAMGuy]

Not to diminish the gravity of the topic, but it reminds me of a funny that I heard some years ago. I was an ATC at the time and an arrival reported passing a flock of birds on the approach. I asked the pilot what direction they were travelling so I could inform other traffic. The pilots response was "Some were going up and some were going down!" Thought that was pretty humurous! :p

[Canuckbirdstrike]

Sevenstrokeroll, mcuh of what you discuss is in print. Go to the Transport Canada website:

Wildlife Control - Transport Canada (http://www.tc.gc.ca/eng/civilaviation/standards/aerodromeairnav-standards-wildlifecontrol-menu-931.htm)

Specifically, read "Sharing the Skies" and you will find lots of factual information on the subject.

As for the suggestion of a large bank angle as a countermeasure for an encounter with a flock of bird, I suggest the outcome is not known. Assuming migratory birds will behave in a consistent manner when startled/threatened is foolhardy. Further, the high bank angle and damage to an engine or flight controls is a recipe for a disaster. A better strategy is to trade speed for energy and climb.

[sevenstrokeroll]

I'll have to read that stuff from transport canada.

in the US we don't have any bird training!

the climb is a good maneuver too. my bank thing takes into account the chance that you are descending or unable to climb due to traffic. certainly climbing is an option not to be over looked.

I do think banking the plane and ending up with an engine out isn't terribly dangerous...certainly something to get your attention though. climbing reduced options sometimes too.

just trying to spur conversation on something we don't cover all the time.

[EW73]

Similar experience to Centaurus...on the same runway!

I was just at touchdown on RAAF Edinburgh runway 18, in a P3 and a flock of seagulls suddenly appeared from the right, and we went right thru them.

Those large paddles at low airspeed flight idle really cleared the way, sustained no engine damage at all, just a whole heap of birds tangled in the gear.

Though, in all my years of flying P3s at all sorts of very low altitudes, down to 30 feet RA on more than one occasion, and with numerous times flying around 300 feet along beaches for some distance, and especially investigating illegal fishing boats (with the associated giant flocks of birds in their immediate vicinity)...

I found that the birds always dived when approached by our aircraft, some left, some right, but always down...so it was a standard maneuver to climb when faced with unexpected (as they always were!) birds.
In 5,600 hours on P3s in this environment, I never had a birdstrike that did any real damage, I was lucky!

EW73 :)

[sevenstrokeroll]

EW73

I agree with you. In my first post I mentioned that birds always dive and that climbing is a good maneuver if available.

my first plane ride was in 1963 in the P3's brother, the Lockheed 188 Electra....the only way to fly!

I seem to recall that an Eastern airlines Electra sucked starlings at Boston and went down.

thanks for coming to this thread.

[Chris Scott]

Nice one, sevenstrokeroll, but no one has raised the issue of lighting. To be visible to the birds must be important (they're not stupid), but are daytime landing lights a help or hinderance? And how about turn-off lights only (not available in flight on the A320 family)?

[sevenstrokeroll]

interesting chris...out of habit I always have all lights on for takeoff and landing and below Positive Control Airspace (FL180 in usa). (fog and odd vis situations aside).

its too bad that A320 can't put all lights on in flight.

[misd-agin]

Birds tend to tuck and dive. Not 'always'. However, they also underestimate the closure rate of 150-350 MPH, so they actually gain little vertical seperation.

60 degrees of bank? First time I've heard that one, especially in an airliner.

Can we be drug tested for posting on MB's?

[Canuckbirdstrike]

Lights are beneficial at increasing aircraft visibility. Radar does nothing. The challenge we face is that new aircraft engines are quiet which removes one other bird sensory mechanism for detecting aircraft.

I still do not support the bank angle method for mitigating possible bird strike damage to engines. Climbing will work, and you do not need to climb much at all even 150 feet will work. think of it like a TCAS climb maneuver.

I must fully support reporting of bird activity. I have been very active in bird strike safety work for many years and I cannot begin to describe how frustrating it is to hear of another serious bird strike event where either the operating crew, other pilots or other people saw the birds and did not report them.

US Air 1549 had a great outcome - no serious injuries or death. The next time may not be that way. There will be a next time and sooner than we think. The next round of migratory movements are already starting and in many urban centers waterfowl are resident.

[sevenstrokeroll]

misdagain

the bank angle is suggested to move the engines out of the plane of the bird formation...climbing is great when you can...but lets say the ''spott' of birds is constant in your windown and you are already climbing the best you can??????

I would also like to think the average atp could handle 60 degrees of bank in an emergency.

[Chris Scott]

Quote from Canuckbirdstrike:
Lights are beneficial at increasing aircraft visibility... The challenge we face is that new aircraft engines are quiet which removes one other bird sensory mechanism for detecting aircraft.

The biggest I ever struck, fortunately, was a migratory Stork, one of a flight of seven or eight. We were all heading north over the Sea of Marmara to Istanbul, so they wouldn't have seen us or our lights as we caught them up from behind. CFM-56s are fairly quiet on the approach. 5 went right; 2 went left; one hesitated briefly. Pity: could have missed him easily if I'd gone around.

Perhaps we need a loud, multi-pitch horn! (The ground mechanic horn works in the air but is too feeble... I did use it once successfully on the ground when a bird blocked the taxiway.)

[CaptainDan80]

You experts crack me up, I have passed and hit many birds in my 20000 hours and there was never time to avoid them, and 60 degrees? You will have fun explaining that at the hearing and if you injure a PAX or FA you are hosed.

Dan

[K_9]

You experts crack me up, I have passed and hit many birds in my 20000 hours and there was never time to avoid them, and 60 degrees? You will have fun explaining that at the hearing and if you injure a PAX or FA you are hosed.

Dan
I'm just a Cessna/Piper driver, but I would tend to agree that doing a quick roll into a 60° bank instead of just climbing or descending sounds pretty foolish, especially on the big iron with pax in the back. I've had an encounter or three with birds on final or just after takeoff and a quick pull up or pushover has always been sufficient.

[sevenstrokeroll]

the purpose is to talk about things like this. so, why didn't "sully" climb?

he was already climbing...not much left to give. I have proposed a method to take the engines out of the formation of birds.

no one wants to hurt a FA and I would hope that in a ''sully'' like situation the passengers would be strapped in?

and if you could avoid hitting another plane, wouldn't a bank be used (if appropriate...asuming no TCAS) even at the risk of a FA being knocked off her feet?

Believe me, some of my best friends are FA's...

[PJ2]

CaptainDan80;
You experts crack me up...FYI, Canuckbirdstrike is probably the finest expert on birdstrikes on PPRuNe.

In addition to sevenstrokeroll's excellent suggestions, (tho' not sure of the 60deg bank!), I would add that keeping the speed at/below 250kts below 10 preserves greater chances for lesser damage in any collision. I've seen 350kts @ 6k in the data and it really makes one wonder what, (besides potentially a bird) what's going through their minds...

http://batcave1.smugmug.com/photos/1085646101_TjxZw-M.jpg



interesting chris...out of habit I always have all lights on for takeoff and landing and below Positive Control Airspace (FL180 in usa). (fog and odd vis situations aside).

its too bad that A320 can't put all lights on in flight.
sevenstrokeroll, I believe it is law in Canada and the US to have all lights on below 10. I agree with you in the US and had mine on until FL180 as well. Though they really rumble, the A320's lights can be extended up to VMO, so all the aircraft's lights are available for flight.

PJ2

[CISTRS]

in the US we don't have any bird training!

Back when Pontius was a pilot, we trained the birds to behave properly.
Today's birds show no respect. :ok:

[Tarq57]

I've only flown lighties, too, but one thing I've noticed with all bird encounters except one, was that a bank immediately prompted the birds to bank away in the opposite direction. Maybe 60 degrees would be necessary to move an engine out of the strike plane, but less might be adequate if dealing with birds that have perceived the approaching a/c?

I guess they know P of F pretty well, and are interested in avoiding what they (often too late) perceive to be a predator.

The one time mentioned above was a large hawk crossing final in front of me, left to right. We eyeballed each other. He wasn't going to give way. I did. He just carried on, victorious.

As a tower controller I gave a bird warning to the crew of a departing 737 once, he would've been above 100kt, I guess, and there were about 4 large gulls crossing the runway ahead, about 100ft AGL. He passed on thanks afterward, and mentioned that he'd adjusted the rotate so as to go under them. The birds acted agitated as he'd approached, but there was no clear cohesive avoiding action taken by them - it all looked fairly random.

[STBYRUD]

I am unfortunately based in a city which seems to be the favourite stopover of millions of migratory birds, had a few close calls last season (lots of bloody noses (our aircraft), a whacked Kruger flap (bird bounced off and hit the engine cowling), but thankfully no surging engines or broken windshields - and from my point of view there is not much you can do. Before takeoff, if you see a flock of birds sitting by the side of the runway, I guess you can only really alert the tower and hope he sends the inspection vehicle to scare them away, on rotation, you might be able to adjust your rate in order not to hit as many birds... In the air? Unless on final approach in landing config from what I have seen the tiny dot on the windscreen gets bigger so quickly there isnt anything you can do about it anymore. Someone tell me please, were you guys serious with 60° of bank? Try explaining that to your chief pilot, seriously. What if you lose an engine in that situation? Don't even want to think about it...
About the weather radar - I suspect the old , high powered radars fitted to older airframes might actually cause discomfort even to people standing dozens of yards away, but the new, extremely low power WXRs? I doubt the birds would notice...

[Chris Scott]

Quote from PJ2:
Though they really rumble, the A320's lights can be extended up to VMO, so all the aircraft's lights are available for flight.

My first post was poorly worded. What I had in mind was that turn-off lights are particularly useful bow-conspicuity devices at night (and lights are still mandatory in the US below 10,000ft?). The problem with the A320 family is that they are attached to the nose-gear leg, so are not available in the climb; only on the approach.

And yes, the landing lights/taxi lights do rumble enough to provoke the odd comment from cabin crew (particularly in those happier days when the cockpit door was unlocked...).

[lomapaseo]

And yes, the landing lights/taxi lights do rumble enough to provoke the odd comment from cabin crew (particularly in those happier days when the cockpit door was unlocked...).

keep in mind that there have been very few severe incidents for transport AC (by regulatory definition) associated with bird strikes on landing. Given these low statistics I'm not a fan of changing the way we fly and introducing added unknown risk in the change itself.

[GarageYears]

So a question:

At 250kt, you are traveling 421 ft/sec. At what distance is the "average" flock of birds visible? In other words how long have you really got to react? At a mile you've got a little over 12 secs... but I doubt you see anything that small that far out?

In reality are you looking out the window with sufficient focus to see and take avoiding action anyway?

I am a little disturbed by the idea of a 60 degree bank avoidance maneuver to say the least...:ooh: ... I have visions of Starbucks coffee flying all over the place, along with sundry other items, small children and crap falling from overheads. :ouch:

Has anyone seen any research on whether avoidance maneuvers are effective - a climb seems the least problematic, but on aircraft with under-slung engines does that simply move the engines inline with the problem?

Now the idea of training the birds.... :ok:

I've tried the same with the deer that seem to populate my street. They used to have a habit of jumping out at the most inopportune moments, but after meeting one face-to-face while walking the dog late one night (damn thing was near invisible in the dark), and having a few stiff words, they seem to be behaving themselves lately...

- GY

[rooaaiast]

Having read the above IMHO I would like to make a few points.
The first is to separate damage to the airframe from damage to the engine.
To reduce airframe damage ( which is usually non-catasthropic for flight safety) it is best to keep 250kts below 10,000', to reduce forward speed- 1/2mv^2 etc.
Engine damage, particularly double-engine strike damage is much more serious. The most important factor is to reduce the tip rotation speed by reducing engine power to the minimum possible for safe flight.
It is official Airbus policy ( apologies I can't find the Airbus Safety Bulletin just now on the Web, but it is there somewhere ) if encountering birds on approach , to continue at as low an engine power as possible.
Under no circumstances is a Go Around at high power to be attempted.
This has been my company's policy (A320/330) for a while now.
With regard to the "60 bank", good luck to anyone trying that in O'Hare on 27L, with an AA777 on port on 28 and a UA/(Connie?) 757 on 27R on starboard !
Hope this adds some light.

[K_9]

I am a little disturbed by the idea of a 60 degree bank avoidance maneuver to say the least...:ooh: ... I have visions of Starbucks coffee flying all over the place, along with sundry other items, small children and crap falling from overheads. :ouch:
What airline is this? I can't believe I never thought about putting those noisy buggers up in the bins! :ok:

[GarageYears]

Quote:
Originally Posted by GarageYears http://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/buttons/viewpost.gif (http://www.pprune.org/tech-log/442589-jet-bird-evasive-action-post6280399.html#post6280399)
I am a little disturbed by the idea of a 60 degree bank avoidance maneuver to say the least...http://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/smilies/icon25.gif ... I have visions of Starbucks coffee flying all over the place, along with sundry other items, small children and crap falling from overheads. http://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/smilies/shiner.gif

What airline is this? I can't believe I never thought about putting those noisy buggers up in the bins! http://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/smilies/thumbs.gif

Ha! Yeah - perhaps the "preview" button might have been prudent, but then again it's not such a bad idea...

;) - GY

[sevenstrokeroll]

this thread is picking up and I am glad.

more people, pilot input etc.

regarding the 60 degree bank...so many are concerned about it. would 45degrees make you happier?

the point of the whole thread is to keep your plane safe and flying. sully sucked birds in both engines...while clmbing is a great idea...MOST OF THE TIME...when you can't climb, would putting the engines (if underslung) out of the bird formation be a good thing? I offered the bank as one way of saving at least one engine.

you of course would have to know if you would bank right into another plane...the same thing for climbing.

but I am very glad people are thinking here.

as far as telling the chief pilot anything, I would just refer to the emergency authority of the pilot in command...the birds were not complying with an IFR clearance and I was...I had to do something!

;-0

[Lord Spandex Masher]

while clmbing is a great idea...MOST OF THE TIME...when you can't climb, would putting the engines (if underslung) out of the bird formation be a good thing? I offered the bank as one way of saving at least one engine.

If you encounter a flock and try banking to avoid them then you're just as likely to put your engine(s) in the way of another bird, you know the one you can't see/hun in the sun kind of thing.

Most of the bird encounters I've had have been during the final approach or immediately after airborne. So flying at or about Vref or V2 and 60 degrees of bank isn't where you want to be is it? That's rhetorical.

Any other bird strikes I've had have generally been medium level 250-300kts and there was NO time to maneuver several hundred tonnes of aeroplane.

It's a nice idea but trying to outmaneuver a seagull in tonnes of unmaneuverable aeroplane isn't going to work.

[GarageYears]

Any other bird strikes I've had have generally been medium level 250-300kts and there was NO time to maneuver several hundred tonnes of aeroplane.

It's a nice idea but trying to outmaneuver a seagull in tonnes of unmaneuverable aeroplane isn't going to work.

Ah ha :D

That was my point. Traveling at 420+ ft/sec in a very heavy airplane is going to take more than a few seconds to significantly change direction at which point you either have or have not hit the dang birds anyway, and if you did, you may find yourself in a significantly compromised position, so perhaps being in a straight and level attitude is preferable to a 45 degree bank - nasty if the low-side engine sucked in a goose...

- GY

[sevenstrokeroll]

but the sully scenario was at 3000'...not takeoff per se, not landing...

anyway...great discussion...

[bubbers44]

I flew into the most turkey buzzard flocks of birds flying into the Tegucigalpa, Honduras valley and even though my chief pilots grounded a few airplanes with bird strikes, I never did. I looked way ahead of the airplane and also asked the FO to look for the dots of buzzards. We always avoided them except once when at 500 ft on take off with the FO flying this buzzard was in front of us and we turned opposite our clearance to miss him. He turned with us so we reversed to our departure clearance and he reversed his flight path and hit about 2 ft. over my head in a 757. We stayed at a lower altitude because the 4 lb bird could have busted some rivets. Yes you can avoid birds if you look out the window. He said I will climb, they always dive. I agreed. This one didn't. Sully didn't see the birds. I have missed thousands flying between flocks and looking out the window. Honduras doesn't load you down much with frequency changes to distract you.

[sevenstrokeroll]

look out the window...the best advice so far!

I think the turkey buzzard wanted to be ''friends'' with you r757~...but it got a bit rough!

[rooaaiast]

*
www.airbus.com/.../AirbusSafetyLib_-FLT_OPS-OPS_ENV-SEQ05.pdf
*
Airbus Flight Operations briefing notes Operating Environment Bird Strike Threat Awareness
*

[411A]

In my considered opinion, large excursions of the flight path of a faster moving jet airliner, to avoid potential bird impacts, is highly unlikely to be met with favorable results.
IE: the pilots can't see 'em in time, and the maneuvering to avoid is chancy, at best, dangerous quite possibly.

So...forgetaboutit.

Usually, the 'maneuver to avoid' scenario is dreamed up by some MSFS amateur, and not a real-world airline pilot, with considerable flying experience in his/her profession.

[sevenstrokeroll]

i'm not an msfs guy

i'm trying to figure a way to avoid bird ingestion in the following scenario

see birds with time to act

unable to climb because of energy or traffic or other considerations

and a way of getting the engines out of the bird formation...at least one of the engines anyway.

I seem to recall (correct me please) that someone on sully's flight commented on what a nice formation the birds were in.

if you have time for a comment...there MIGHT be time for a well considered maneuver.

[K_9]

i'm not an msfs guy

i'm trying to figure a way to avoid bird ingestion in the following scenario

see birds with time to act

unable to climb because of energy or traffic or other considerations

and a way of getting the engines out of the bird formation...at least one of the engines anyway.

I seem to recall (correct me please) that someone on sully's flight commented on what a nice formation the birds were in.

if you have time for a comment...there MIGHT be time for a well considered maneuver.
The problem is that in reality you will never have enough time to do these maneuvers you're dreaming of. A 777 isn't an Extra 300, and even if you could make that roll by the time you got to the birds you were trying to avoid, a 60° bank is not where you want to be on short final or just after takeoff, particularly if there's a highly increased likelihood of losing an engine. Besides, you don't know which direction the birds are going to go, and if it's a flock of them they're probably going to scatter in ever direction, negating the "benefit" of the steep bank altogether.

[Chris Scott]

K_9, I agree with your arguments.

Does anyone happen to know if Sullenberger's birds were opposite-direction, same-direction, or "crossing traffic"? In my Istanbul approach case (see above) we caught the Storks up from behind, so they may have been unaware of our presence until they heard our engines (too late).

I'm wondering if there is any evidence that bird formations will peel off to avoid a conspicuous, giant bird coming at them. They may not be as stupid as we assume. Either way, we are so quiet and fast that they may not see or hear us in time if we are coming from behind.

This may sound frivolous, but has any research been done into the possibility of some kind of aural warning from aircraft? What is the current state of play on aural bird-scaring at airfields, and could similar technology be used from the air? This would depend on the crew being aware of the confliction, of course, so would only work in a minority of cases. We wouldn't be very popular if all the quiet-engine technology was wasted by a constant, fog-horn-like racket on all departures and arrivals... That being the case, is there any type of short-range radar or infra-red device that can detect birds, and issue a warning to the crew? Perhaps Canuckbirdstrike can answer some of the above.

[aviatorhi]

Going off my previous comments on this subject, and in agreement with what 411a said, in a jet you're not gonna see them in time to do anything about it, like I said, I've seen people try, didn't make a difference (maybe they would've even missed if nobody tried rolling the plane a bit), I once tried to avoid a flock in a 1900, but we were only doing 120 knots at the time so I just pitched down a bit and flew under them, did the same doing about 100 knots in a 207 at 2000 feet off a cliffside where they like to nest. I think that, realistically, there is a speed limit as to where you can see one in time and do something useful about it, needless to say, 99/100 jet aircraft are going beyond that speed limit.

[Machinbird]

Gents,
You can see the birds in time, in my opinion, if you are looking for them in the right spot. Admitted, I'm a tactical jet aviator, not a big iron one, but if I can get my aircraft AND my wingman's aircraft over a cluster of buzzards while flying in towards the airfield at 250+ knots, you can get your big iron bird over the top too. Perhaps when everything is down and dirty, we both don't have a lot of options, but the key is acting positively and early.
As I mentioned early in this thread, the spot that you have to scan for birds is small and is directly ahead of your aircraft. You have to continually be giving this spot the close eye in bird country. You should take the effort to get your glasses prescription tweaked to better than 20/20. The big birds can usually be seen in time unless they are flying IFR or at night. Hitting the smaller, less visible birds, has fewer consequences, normally just need to clean the red streak off the airframe.:}

[Canuckbirdstrike]

The challenge with any system to warn and deter birds is habituation. If you use noise or other harassing techniques eventually the birds learn or habituate to the fact that this noise is not a threat, just a nuisance. Much like the "snake oil" salesmen of the previous century there are many manufacturer's with wild claims on various sound based systems deterring birds. There is no data from reputable scientific studies to back these claims.

To illustrate how clever birds are at figuring this out. I sat one day in the line up for takeoff at a major airport that used propane cannons that automatically rotated and fired to scare birds. I watched a seagull sitting on the end of the cannon riding back and forth as it moved. Then it would fly off, let the cannon activate and then fly back to his perch and enjoy the view and look for food. I took the time to visit with the wildlife control personnel at this airport and watch the event up close. The bird was smart enough to hear the propane valve open to let the fuel into the chamber and realize that is what triggered the noise. He just learned to work the system.

Deterring birds at airports is hard work. It is guerrilla warfare and you have to constantly outsmart your enemy and change tactics. The problem is that in our instant, virtual world everyone wants a one stop automatic solution. For birds and wildlife there is not one.

So putting noise makers on aircraft will not work. First from the wildlife perspective and secondly for the fact that with aircraft speeds the sound will not reach the birds in sufficient time.

Encounters with birds above 1,000 ft AGL are not within the area where ground based strategies will work in general. In some cases if you can remove an attractant (food or shelter) then the flight path may get modified, but this is a long term and challenging activity. At altitude detection and avoidance is the strategy. Significant work has been and continues to be done with avian radar system that have species detection and bird flight path prediction capabilities. The technology is being used in trials at some airports, but it is expensive and to date no one has bothered to consult with the aviation industry in a meaningful way on how we would use this technology in practice.

[Chris Scott]

Thanks Canuckbirdstrike, for your insights.
Quote:
If you use noise or other harassing techniques eventually the birds learn or habituate to the fact that this noise is not a threat, just a nuisance.

I was looking at the problem from a different angle: that of INFORMING the birds of our presence, i.e., an attention-getter; not trying to TRICK them by, for example, mimicking the sound of a raptor. My idea does not itself involve any attempt to curtail bird activity on airfields, which is evidently futile.

You have illustrated the intelligence and learning capabilities of birds. Is there any evidence that they will continue on course deliberately towards what presumably resembles a large, strange bird?

You argue that, with aircraft speeds, the sound would not reach the birds in sufficient time. If crews are to continue relying on Mk1 eyeball, time is definitely of the essence. In clear-visibility daylight, a small flight of medium-to-large birds might be visible at about a mile or so? In my Istanbul case, I distinctly remember having time to weigh up the options. With our lights all on, experience suggested they would peel off in good time. But – probably because we caught them up from behind and they didn't see us – they left it very late. My guess is that the first they knew of us was our all-too-modest engine noise.

A bird-detection system like airborne avian radar might work in any visibility, and detect at several miles. At a range of 3nm, the attention-getting sound would take just over 15 seconds to carry; at 180 kts, the aircraft would arrive about 45 seconds later.

I presume any suitable speaker/megaphone would create drag and be vulnerable at high IAS, so perhaps it could extend and retract with the landing lights.

[GarageYears]

A bird-detection system like airborne avian radar might work in any visibility, and detect at several miles. At a range of 3nm, the attention-getting sound would take just over 15 seconds to carry; at 180 kts, the aircraft would arrive about 45 seconds later.For a sound to audible at 3km distance.... yikes.... let's say you want the volume to be 80dB SPL at 3km, which is nice and loud but not excessive, you'd need the volume at the SOURCE (i.e. the aircraft) to be 143.5dBSPL :mad:!!!!! Think SATURN 5 lift-off kind of volume.

(Sound drops 6dB with every doubling of distance)

That is seriously loud!

And remember sound drop-off with distance is also frequency dependent, so if your intent was a high frequency laden sound, then it would have to start off even louder.

Any speaker used is going to struggle also with the effect of airspeed impeding it's ability to function in the first place - you'd have to use some kind of compression driver, which by nature need to be horn-coupled to achieve reasonable volume - sticking a biggish horn (one able to generate 140+dB) is not going to do the aerodynamics much good, let alone what your passengers might think. :zzz:

- GY

[Canuckbirdstrike]

The key with bird sensing and responses is linking what they sense to a threat. If not threatened the birds will not react.

Birds are not inherently programmed to perceive an aircraft as a threat.

Reprogramming bird behaviour on a global basis is not particularly possible.

[Smudger]

60 degrees of bank in an airliner is a NO NO for many reasons... approach speed, passengers, low aileron roll rate at that speed.. come on... just have all your lights on and apply some airmanship given the info on birds that atc have given you or that you can see... or whatever.. there is no checklist for this situation

[Chris Scott]

Garage Years,
Thanks for your comments. I have to admit to being ignorant on sound propagation and energy levels. I understand your point that, if an observer doubles his distance from the source, the perceived sound energy will be a quarter (-6dB), but can't get my head around what happens very near the source. By the way, I had in mind a very directional one, if possible, using some kind of megaphone. The sound would be concentrated as much as possible into a flattened cone about 30 deg wide, and 10 deg vertical. Would that help?

Canuckbirdstrike,
Thanks for expressing the problems so clearly and succinctly! Bird psychology is also beyond my ken. So is your answer to my question: "Is there any evidence that they will continue on course deliberately towards what presumably resembles a large, strange bird?" a definite "YES"?
If not, here's another: on hearing a loud, unfamiliar sound, do birds turn their heads and look for the possibility of danger?

Chris

[GarageYears]

By the way, I had in mind a very directional one, if possible, using some kind of megaphone. The sound would be concentrated as much as possible into a flattened cone about 30 deg wide, and 10 deg vertical. Would that help?

Unfortunately in terms of sound level, the distance law applies irrespective - the shaping of the source simply helps determine the initial dispersion pattern - in this case the sound would be directed 'forward' initially, however since sound is a pressure wave, at any significant distance the dispersion pattern becomes more or less 360 degrees (free space - you still "hear" the sound from any loudspeaker enclosure whether in-front or behind - you just lose a little as the sound "turns the corner").

(I am ignoring some aspects of frequency here - higher frequencies tend to travel in what I like to think of as straight lines, whereas low frequencies "bend" much more easily)

Cheers, GY :)

[Skittles]

GarageYears,

You are referring to the inverse square law? Or at least a variation on the theme?

Cheers.

[Canuckbirdstrike]

Chris, simple question complex answer. Different birds have different reactions to stimulus, sound, sight or smell. The answer is further complicated by whether it is a solitary bird or a flocking bird.

As for birds perceiving aircraft as large strange birds, the jury is out on this, We cannot get inside a birds brain and really determine what they think an aircraft is. Further, no detailed studies have been done on this and of course each species would have to be individually researched.

I know I have not answered your question because you are looking for a "one size fits all" answer and in the world of birds and mammals that does not happen.

[Tarq57]

I've seen quite a lot of bird nearmisses, as a tower controller, and quite a few strikes. (And in one case a bird death apparently resulting from a loss of control/ground impact after a wake turbulence encounter. Oyster catcher vs B732.)

Different species of bird definitely exhibit different behaviour when an airliner is about to share their airspace, ranging from apparent oblivion, through random scattering, to an intelligent appearing and timely avoiding manoeuver. That last is rare. Usually the bird avoiding action, once it has perceived the aeroplane, occurs as or after the aeroplane passes.

I haven't particularly noticed if flocking makes a difference, although it appears that some birds flock together in a cohesive avoiding action (Starlings and pigeons, for example), others randomly scatter and others seem to become agitated, yet seem stoically to refuse (or unable) to break formation, like Canadian geese.

This would make an interesting study, for sure. (Is anyone doing it?)
I know from experience (mentioned several posts back) that some types of birds will immediately turn, together, if the aircraft heading toward them starts a turn the other way. It doesn't need to be a 60 degree bank. They start turning as soon as they register the bank...maybe 5 degrees, if that. And in one story above, concerning the Buzzard, the bird turned with the aircraft. Twice. (The dumbass.)

[cosmo kramer]

The one time mentioned above was a large hawk crossing final in front of me, left to right. We eyeballed each other. He wasn't going to give way. I did. He just carried on, victorious.
Well, he had the right of way - didn't he? :)

if you are head on with a formation of birds, bank YOUR plane about 60 degrees
I have to agree that this is the most ridiculous suggestion I heard. 280 knots climb and any abrupt maneuver with any bank angle, the likelihood of much more severe damage than a little dent in the leading edge!

Fly through the buggers and hope for the best (for their sake, I always feel bad killing a fellow aviator :().
We been flying jets commercially for 60 years and the one Hudson incident, the statistical evidence doesn't warrant any of the risk suggested here.

Keep the speed down if there are many birds and put the lights on, are the only valid suggestions in this thread. Most of the time where you are actually able to see them is on final when the speed is low. Maneuvering to avoid would be absolutely prohibited, only option would be a go-around. Even this may be a bad idea, unless you are absolutely sure that it will avoid them (let say that you see a flock of 1000 birds sitting on the threshold when you are still at 500 feet). Going around when it's too late (birds already in the air in front of the windows), may only increase the risk since the engines will be at a higher RPM with a much bigger likelihood of severe damage.

[Canuckbirdstrike]

Lots of good discussion here and as always an evolving thread.

The perception that statistically this is not a risk is a flawed argument for two reason; first the data just does not support the assertion and second risk needs to be assessed using the matrix or exposure probability and severity and the use of data to solely assess risk is a flawed methodology.

There also needs to be an understanding of the aircraft certification requirements for bird strikes; engine and airframe. If we confine the discussion to airline category, jet powered aircraft, which have the highest requirements, there are deficiencies in the requirements that are no starting to be discussed.

One of the key deficiencies is the lack of a requirement to consider damage to more than one engine.

The next is that there is no requirement to consider damage to the aircraft AND the engine(s) at the same time.

Accident and incident reports are clearly showing that this is occurring and at a rate that is worthy of design consideration.

I have read many reports of aircraft being damaged after a bird encounter with an engine and aircraft systems such as hydraulic and flight controls damaged at the same time. With a few exceptions the aircraft have been recovered without injury or death.

My point is that as pilots we do need to learn more about this risk.

Take the time read "Sharing the Skies" it has all the salient facts about certification standards and it provides good information on risk mitigation strategies.

It is available on line at the link I provided earlier on in this thread.

A lot of meticulous research went into this book and the material is accurate and verified. I can attest to this personally. I wrote five of the chapters and acted as the technical editor and we were required to validate everything.

No I do not get royalties for the book.....

There is also lots of other material available out there at the various national and international bird strike committees websites.

[misd-agin]

60 degrees of bank? Number of the hundreds of pilots I've flown with that have done that? Zero. I think they're onto something.

[JuergenP]

50mm canon works well...

[sevenstrokeroll]

certainly transports should only rarely exceed 25-30 degrees of bank...but they, and I would like to think most ATP's, are capable of that.

if your plane can't handle a 60 degree bank...better find a new plane!

you might not even get to 60 degrees of bank while attempting to move your engines out of the plane of the bird formation...but it is an idea when other maneuvers are not suitable.

[lomapaseo]

The perception that statistically this is not a risk is a flawed argument for two reason; first the data just does not support the assertion and second risk needs to be assessed using the matrix or exposure probability and severity and the use of data to solely assess risk is a flawed methodology.

There also needs to be an understanding of the aircraft certification requirements for bird strikes; engine and airframe. If we confine the discussion to airline category, jet powered aircraft, which have the highest requirements, there are deficiencies in the requirements that are no starting to be discussed.

One of the key deficiencies is the lack of a requirement to consider damage to more than one engine.

The next is that there is no requirement to consider damage to the aircraft AND the engine(s) at the same time.

Accident and incident reports are clearly showing that this is occurring and at a rate that is worthy of design consideration.



A lot of this is correct but:

There are many factors combining together that establish risk and to selectively cite some while excluding others is also not statistically valid.

Yes even I am guilty of that in the desire to KISS the subject as posted (unplaned manuevers as an escape from a historic risk)

It is also true that the regulations do not cover all possible combinations of birds, engines and aircraft systems. That is the nature of how regulations are developed for varriable enviromental threats. Thus the regulation and design intent is to take into account how often really bad stuff has occured in the past and to provide a modicum of capability within a balance of avoidance. There are many other risks to flight safety which are competing for attention at any given time so the intention of evaluating changes to our response is necesarily proritized towards the low hanging fruit on the tree.

Keeping with this ideal, any of us can put forth new ideas for addressing the risk and then evaluating how much benefit we can expect vs introducing some unknown new risk.

I'm open to suggestions for such risk reduction within the confines of this thread subject or even expansion if so stated

[sevenstrokeroll]

do we think it is safe to say that the high bypass fans /engines are more susceptible by their nature to sucking bigger birds?

my first jet (NA 254-40) had small inlet engines and a nice cross of metal (if you will) that would easily slice a bird up coming in to the fan/compressor section.

the JT8D as we have talked about has such a small inlet compared to the CFM<56.

etc.

[411A]

...you might not even get to 60 degrees of bank while attempting to move your engines out of the plane of the bird formation...but it is an idea when other maneuvers are not suitable.
Hardly.
Imagine, being on the ILS (in good weather) at LAX on 25L, with another jet on a visual at the same time on 25R (wing tip to wing tip) and our intrepid pilot on the ILS on 25L...decides he needs to maneuver to avoid birds...at 900 agl...off to the right.
BANG.
It's all over, except for the post mortim on the dead bodies.
Sorry, sevenstrokeroll, you might be a nice guy and all, but....very poorly thought out with a big jet airplane.
NB.
And yes, I've been wing tip to wing tip at at LAX...on the 25's...with a 707.
DC-8 opposite.

[Canuckbirdstrike]

Lomapaseo, valid points, but there is already activity in the industry on the issue of bird strike certification standards not being adequate.

I have considerable experience working in the regulatory environment and fully appreciate the parameters that drive regulatory change.

Sadly, rather than really understanding the US Air 1549 event and making meaningful changes to airport wildlife control requirements, training for the industry and revising certification standards, we continue to ignore what the data and risk assessments are telling us.

I fear that the only way this issue will get the traction it needs is a tombstone safety event with lots of casualties. we have not had one in recent memory and US Air 1549 only became a book and a movie (pardon the sarcasm).

Curiously no mention of the Ryanair event in Rome the November before US Air 1549 is made. Another double engine failure from birds with another successful outcome. There are many other disturbing incidents, the frequency of which is increasing.

How long do you want to keep rolling the dice........

[sevenstrokeroll]

411A

you missed the boat. I offered the bank as an escape maneuver when other options wouldn't work...imagine if that 707 was over your head and you pulled up to avoid the birds...and now you both have TCAS and it issues an escape maneuver.

a pilot needs many things in his bag of tricks and I was offering a new one to consider.

KLAX, KSFO...lots of airports are side by's.

[lomapaseo]

How long do you want to keep rolling the dice........

frankly .... forever

The world is imperfect, always was and always will be.

Rolling dice is just one of the imputs that we use in a monte carlo stastical system to prioritize what we work on. Of course such a system needs data but nobody intends to wait and count enough tombstones. Thus the pointer data is at a level of risk where no lives are lost since critical factors being missing or something worked as planned (pilot training etc.)

The regulations need to keep up with measured changes either via mother nature, operation or product capability. Since the data to support such changes as well as expert manpower is available these regulatory changes will keep on being updated every 5 years until /unless ignored shortfalls in other areas capture the attention of the I told you sos.

I sense that the work on the engine side of the regulatory function will soon make it more likiely that multiple bird strikes on the aircraft as well will combine with the engine side of the systems and result in accidents. There is already data available in this arena.

[lomapaseo]

do we think it is safe to say that the high bypass fans /engines are more susceptible by their nature to sucking bigger birds?



To ingesting bigger birds the answer is yes (it's more of a capture diameter thing than bypass or thrust)

However the bottom line is the capability to operate in a natural environment and that brings into play the susceptibility to critical damage.

Keep in mind in the transport side of things the birds are not inantimate objects but will take some kind of evasive action albeit not always the safest zig and zag. Couple this with the change in dynamics to the engine blading if the bird happens to intersect a solid structure on the way into the engine and turn itself into much smaller pieces (Hudson River).

The idea behind the regulation is to provide a relatively flat field of risk accross the various engine sizes and types else by hit or miss we would just regulate out certain size installations of engines and drastically alter the industry and air travel.

[411A]

...a pilot needs many things in his bag of tricks and I was offering a new one to consider.


And, a very poor one, at that.
Back to your MSFS.:rolleyes:

[sevenstrokeroll]

time to thank everyone who has a genuine interest in this topic.

[Chris Scott]

Quote from irishpilot1990:
The result could be situation with both engines damaged that you have insufficient power and runway disappearing beneath, in general continue unless reasonable happy birds will be avoided!

As you're not pulling your own punches, I'll just say that the above is incoherent, even by the normal standards of these threads. If you want to dish it out, at least try to improve your syntax!

[ShyTorque]

Unless you have JT8Ds slung on your airplane, then you can plow through anything.

No, you can't. I lost a good friend in this accident, dating back to 1980:

18 November. XV 256 crashed on take off. The aircraft suffered a major bird-strike immediately after take off and crashed into a wooded are to the east of RAF Kinloss air base. Sadly, both pilots were killed but, due to their skill in controlling the crash, the remainder of the crew escaped. Posthumously, Flight Lieutenant Anthony, the flying pilot, was awarded the Air Force Cross and his Co-Pilot, Flying Officer Belcher, the Queen's Commendation for Valuable Service in the Air.

(Copied from the RAF Kinloss webpages)

This was a four engined Nimrod, the first one we lost. From my own memory of the accident report, 72 dead gulls were found on the runway.

I picked up a number of Harrier Pilots and flew official photographers at accident sites in RAF Germany in the early 1980s when aircraft were lost due to Pegasus engines being terminally damaged by bird ingestion.

Also, the large flocks of Canada geese living on ponds to the south of Heathrow Airport were/are considered a major flight safety hazard to airliners.

Not convinced that radar works as a bird scarer but forward facing white lights do.

[Chris Scott]

Quote from sevenstrokeroll:
do we think it is safe to say that the high bypass fans /engines are more susceptible by their nature to sucking bigger birds?

More birds, yes; bigger birds, I'm not sure.

Another issue is what happens to the debris of the wretched bird(s) after impact with the fan or spinner. Small birds are unlikely to damage the fan blades themselves, but what you don't want is for debris to enter the core of the engine. Although the JT8D probably picks up fewer birds, the CFM56 (with its much higher bypass ratio) probably ejects a higher proportion of impacting birds (and resulting debris mass) through its C-ducts. Passage through a C-duct, by-passing the core, is unlikely to involve further damage, though it may need to be cleaned.

On a CFM-56 walk-round, finding evidence of blood or very slight damage to the leading edge of a fan blade, it was usually considered OK to dispatch the aircraft provided the point on the blade was well clear of the intake to the core. If there was any doubt, a boroscopic inspection had to be called for. (Personally, in any case, I always had a good look up the back end at the LP turbine.) The great thing about the A320 and B737 is that all of this can be done without the need for a stepladder...

(EDIT) PS, re ShyTorque's post
The Nimrod accident at Kinloss was shocking, not least to other Spey fliers (I was on the BAC1-11 then). The Spey, of course, has an even lower bypass ratio than the JT8D. In view of the enormous number of birds involved, I'm not suggesting the engine type was necessarily a factor. But some thought that the Spey was more vulnerable to bird-strike damage than most.

[misd-agin]

"I offered the bank as an escape maneuver when other options wouldn't work...imagine if that 707 was over your head and you pulled up to avoid the birds...and now you both have TCAS and it issues an escape maneuver."

I'm sorry, but you're writing nonsense. "When other options don't work"??? You must have dual Cray computers, along with internal velocity vector information, horizon display, track while scan capability, along with flight test roll and pitch performance data stored in your brain to be able to see a bird, or birds, compute their exact flight path vs. your flight path, compute closure rate, compute offset space generated by manuevering your aircraft and then HOPE the birds stay on the exact course and altitude.

So you do all of this computing, realize the solution isn't working, and decide - "my moment of fame is upon me! Sixty degrees of bank will save the day!"

Wow.

:yuk:

[sevenstrokeroll]

I am surprised that so few people can appreciate moving the engines out of the plane of the bird formation.

people have been saying that I must only fly microsoft flight sim...and not real planes. yet I started the thread. and when I did, no one said I was a microsoft sim guy. (by the way, I know how much the microsoft pilots made! wow!).

shytorque...I thought the engines on a nimrod were in the wing and not slung below...and were they JT8D's/??

411a and irishpilot...so , you say the birs are at low level, usually on takeoff , have I said to exceed the max bank for a safe speed? I made a tragic assumption that a pilot would know the various bank angle limits for a speed/confifguration.

irishpilot...leave the thread or the forum when you like. maybe you have never done a 60 degree bank in any plane.

maybe you need a telephone book to see over the anti glare panel.

[Green Guard]

LAX 25L vs LAX 25R
(wing tip to wing tip)

Just curious, how much would that be in feet or meters ?

[cosmo kramer]

sevenstrokeroll:
I made a tragic assumption that a pilot would know the various bank angle limits for a speed/confifguration.
sevenstrokeroll, this shows a lack of knowledge that makes it hard to believe that you are a commercial pilot (or private for that matter). Anyway, fair enough, since this is not a closed forum. But it would serve you well to ask questions instead and listen when people answer them.

Assuming that you are not a pilot I will politely explain in layman's terms:

1) When at the lowest permissibale speed for the current flap setting there is typically 40 degs bank avialable to stickshaker.
2) The actual number of the lowest speed depends on the actual weight of the aircraft
3) It also depends on the altitude, and may be lower at higher altitudes. Boeing does not correct for this and leaves us to guess how much.
4) If you fly faster than the minimum speed you may bank more, but normally we fly pretty close to the minimum speeds, because when the flaps are out we actually want to fly slow.
5) When the flaps are up and we fly faster than the minimum speed for flying without flaps, there is obviously more bank angle available.

All of the above assumes balanced forces (level flight, steady climb or steady descent). If you are willing to compromise your flight path you may bank as much as you like as long as you unload, since an aircraft doesn't stall due to bank angle but due to airflow seperates from the wing. So again, in layman's terms, if you do not pull back on the controls and trade in altitude you can theoretically bank with 90 degs without stalling at any speed (you won't be doing it for long though). Hope this explanation was not too complicated.

Here is what Boeing find sufficient for us to know:
Boeing:
The following tables contain flap maneuver speeds for various flap settings. The flap maneuver speed is the recommended operating speed during takeoff or landing operations. These speeds guarantee full maneuver capability or at least 40° of bank (25° of bank and 15° overshoot) to stick shaker within a few thousand feet of the airport altitude. While the flaps may be extended up to 20,000 feet, less maneuver margin to stick shaker exists for a fixed speed as altitude increases


sevenstrokeroll: I am surprised that so few people can appreciate moving the engines out of the plane of the bird formation.

Another flawed assumption. What makes you think that the angle you are climbing and the lateral spread of the birds would not cause you to roll the aircraft into the birds instead. Level flight through the flock may have the exact same statistical outcome.

Finally, let's see what Boeing writes about steep turns:
Boeing:
Steep Turns
The objective of the steep turn maneuver is to familiarize the pilot with airplane handling characteristics beyond 35° of bank and improve the instrument crosscheck. During training, 45° of bank is used for this maneuver. It is not intended that the pilot should ever be required to bank greater than 25° to 30° in any normal or non-normal condition.

Case closed. Move on...

[misd-agin]

Figure out the math on the distance between the engine centerlines -

737 - less than 40'
767 - less than 60'
777 - less than 70'

A 60 degree bank would equate to .9 (90%) of the distance between engines.

So what you're saying is you can estimate, within 30 to 60 feet, exactly where your aircraft and the bird will merge. Based on that you then factor in your roll rate, velocity in feet per second, and then roll at the right time to ensure that one engine goes above the perfect line of birds and another goes through, or below, the flock of birds.

:{

If you can figure it out this well why don't you just pitch up and displace the aircraft 30' with a wings level attitude?

[411A]

Just curious, how much would that be in feet or meters ?

250-300 feet, or so, allowing for minor diviations from the runway(s) extended centerlines.
Close enough that you can clearly see the opposite pilot smiling:E...or not.

[Canuckbirdstrike]

Misd-again, Bingo! My point exactly, a small vertical change will put you out of harms way. The same concept as TCAS maneuvers. The concept of aerobatic bank angles is fundamentally flawed from a risk avoidance and safety of flight perspective.

The UK CSL did an analysis on wing mounted engine and possible interactions with migratory bird flocks. The analysis was sobering, hence the need to revisit the regulations and standards to address strikes to multiple engines.

I am trolling through my files to see if I can find the file and post it.

[sevenstrokeroll]

canuck...since when has a 60 degree bank been aerobatic? exceeding, yes...

[cosmo kramer]

sevenstrokeroll, you just don't give up, do you?

More than 45 degs bank is considered an upset in a commercial jet.

Swept wing jet are not the same ballgame as C172. Look at the design load factor requirement. +2.5G is the limit for an airliner, that's 67 degs bank level flight. Or 60 degs with a little too much back pressure.

[sevenstrokeroll]

wow, I've been in alot of upsets then...

you fly your way...even in the plane we train for ''steep turns'' at 45degrees...
and who said 67 degrees? and who said you had to pull back in this situation.

even the 707 was rolled

[K_9]

canuck...since when has a 60 degree bank been aerobatic? exceeding, yes...
Unless you're a flight test pilot, you have no business there when piloting a transport aircraft. I've got 200 hours or so in 172s and Cherokees, and about 20 hours in the engineering sim for a certain widebody airliner I work on (basically has everything a level D sim has but without the motion--we use it for testing systems behavior through various flight conditions). I can tell you that as easy as 60 degrees is in the little guys, doing that maneuver in the widebody is not something that should ever be done in real life. I don't remember exactly how much, but I lost at least a thousand feet when I rolled to 60° and right back to level flight in a clean configuration. Can't even imagine how it would be with the flaps and gear out and at 1.3 Vso

even the 707 was rolledYes, clean high and fast. Do you know how much altitude they lost in that maneuver?

[sevenstrokeroll]

who said to roll the plane to 60 degrees of bank at 1.3vso with gear and flaps out? I didn't .

have you guys even read the original post?

I'm trying to get the engines out of the birds path...it is one option...in the first post I even mentioned climbing.

by the time you started the roll, you would pass the birds and start to resume level flight...perhaps I should have said: NOT TO EXCEED 60 degrees of bank.

wow.

some of the dopiest guys on pprune and they didn't even read the posts

and a guy with 200 hours in cherokees and c172's.

wow...charles lindbergh, move over!

sheesh.
I don't know how much altitude the 707 lost while rolling, but I've seen the film and it looked really nice...twice...in front of all of Seattle. It didnt look like much, but I wasn't looking at the altitmeter, were you?

[Canuckbirdstrike]

By regulatory definition more than 45 degrees of roll is considered aerobatics.

[sevenstrokeroll]

which reg...faa doesn't specifiy...just checked

[Canuckbirdstrike]

I stand corrected on that. I just rechecked and the value is 60 degrees of bank in the Canadian regs.

However, the point is moot because in reality given the roll rate of jet aircraft and the potential for other problems with maneuvering a jet aircraft in this manner, the likelihood of this succeeding is low.

Add to this the fact that the predictability of bird flight patterns when threatened and the birds actually remaining in the same lateral distribution is low and I cannot see any real value in this strategy.

I can see the value in a change in vertical profile to avoid a flock of birds and can speak from practical experience using it.

[K_9]

who said to roll the plane to 60 degrees of bank at 1.3vso with gear and flaps out? I didn't .

have you guys even read the original post?

I'm trying to get the engines out of the birds path...it is one option...in the first post I even mentioned climbing.

by the time you started the roll, you would pass the birds and start to resume level flight...perhaps I should have said: NOT TO EXCEED 60 degrees of bank.

wow.

some of the dopiest guys on pprune and they didn't even read the posts

and a guy with 200 hours in cherokees and c172's.

wow...charles lindbergh, move over!

sheesh.
I don't know how much altitude the 707 lost while rolling, but I've seen the film and it looked really nice...twice...in front of all of Seattle. It didnt look like much, but I wasn't looking at the altitmeter, were you?
I have read the thread in its entirety since the day you posted it. I think it has been beaten into the ground that, at anything other than approach speed, there is no chance you will see birds with enough time to react. This leaves the only possible application of your idea to approach and departure, so unless you will retract your ridiculous claim, you are indeed suggesting to roll into a 60° bank at 1.3Vso.

Unless I missed something, we have yet to hear what your personal flight experience is. I make no secret of the fact that my experience is limited to VFR and IFR ASEL and several simulator sessions on the heavies so that those reading my post know what the context is. Please, tell us what your experience is so that I may properly honor the next Chuck Yeager. If not, you're just a troll who likes to play with MSFS.

[sevenstrokeroll]

dear canuck

thanks for acknowledging 60 degrees of bank (exceeding) as aerobatic...indeed the FAA only speaks of it as requiring a parachute in FAR 91.307

Dear K9...there are countless times I've seen bird formations above 3000 feet, not in either approach or departure. Therefore I do not subscribe to your contention that only in the approach or departure phase could you see and maneuver to avoid birds. Just because it has been beaten into the ground on PPRUNE doesn't make it so. Why not take the time to really look for birds at a distance?

I even remember seeing a small child's balloon (with mickey mouse shape) at FL350 with time to avoid if needed (vicinity of Ontario , California (yes, sort of near, but not that near Disneyland)

AS to my experience:

CFIIMEIATPMEL 737 type rating. I learned to fly in 1975 and am employed by one of the largest airlines in the world as a pilot. Any more would give away my employer's name.

So, polish up your spectacles. And keep your eyes on the sky and not in the engineering books.

[sevenstrokeroll]

as to the sad turn of this thread, this will be my last post. anyone wishing intelligent discourse may PM me.

[K_9]

dear canuck

thanks for acknowledging 60 degrees of bank (exceeding) as aerobatic...indeed the FAA only speaks of it as requiring a parachute in FAR 91.307

Dear K9...there are countless times I've seen bird formations above 3000 feet, not in either approach or departure. Therefore I do not subscribe to your contention that only in the approach or departure phase could you see and maneuver to avoid birds. Just because it has been beaten into the ground on PPRUNE doesn't make it so. Why not take the time to really look for birds at a distance?

I even remember seeing a small child's balloon (with mickey mouse shape) at FL350 with time to avoid if needed (vicinity of Ontario , California (yes, sort of near, but not that near Disneyland)

AS to my experience:

CFIIMEIATPMEL 737 type rating. I learned to fly in 1975 and am employed by one of the largest airlines in the world as a pilot. Any more would give away my employer's name.

So, polish up your spectacles. And keep your eyes on the sky and not in the engineering books.
Thanks for addressing that. However, I have to respond to your last quip--the engineering is what makes your airplane fly and the restrictions that exist are in place for reasons previously discussed.

[misd-agin]

I made a basic mistake in the bank angle math, and how much it displaced an engine from wings level. It's HALF the value I posted. So you're telling me you can calculate where the birds will be within 15 to 35 feet, with enough time to calculate the roll rate needed to achieve 60 degrees of bank before you merge with the birds...wow.

If you're that good and you saw the birds you could do a .5 degree pitch attitude change and in a quarter mile you'd miss the birds by the same amount(12'). But noooo, 60 degrees of bank is the solution you're advocating. :ugh:

PM you for intelligent discourse? :{

[PJ2]

sevenstrokeroll;

By way of intervention, the thread ought not to have been diverted by the 60deg bank issue but instead should have remained focussed on your original, laudable goal of enhancing awareness on the seriousness of bird-strikes.

There have been some very helpful, intelligent comments made here which, we may safely assume, are read by many who nevertheless don't post.

I happen to agree with those who believe that a 60deg bank is not a likely avoidance manoeuvre for a jet transport, for the reasons stated but that in no way negates the substantial contribution of the thread. (BTW K-9, in my experience 60deg bank steep turns were standard in an initial IFR/PPC ride, with no altitude lost/gained, no speed lost/gained. It is NOT a tough manouevre if you know what you're doing and can fly. I just don't think it is practical in a transport aircraft - great coordination exercise though, especially if done while climbing then descending...)

My own view, informed by analyzing flight data and seeing speeds in the data of up to 350kts in terminal areas of major airports (on migratory bird routes), is, (at almost 800fps), "why are you doing this?".

ssr, if the thread causes some to reconsider such a decision to fly their aircraft above 250kts below 10k, it will have been worth the beatings over 60deg's... ;-)

regards,
PJ2

[K_9]

skyfish...what? :confused:

PJ2--I've done plenty of steep turns in my usual airplanes, and I have some dual in an Extra 300 so I've done a wee bit more than 60°, too. As you said, none of that is practical for a transport unless it's a C-17.

[411A]

CFIIMEIATPMEL 737 type rating.
That explains it...small jet, strange ideas.:ugh:

[lomapaseo]

Discussion threads have value in this section even if it results in arguments.

Name calling and/or assignment of personal charcteristics is not an argument, it's a put-down and confuses the technical discussion among those of us that want to consider some new points with pro and cons.

[aviatorhi]

No, you can't. I lost a good friend in this accident, dating back to 1980:

Don't Nimrods have RR Speys?

[john_tullamarine]

It appears that the fascination with 60° has been exhausted for most.

To echo another poster's observation, it is not very useful to descend into name-calling and arm-waving.

Perhaps the thread could return to the more sensible and directed discussion on what is an important topic ?

[bubbers44]

I think the best way to avoid birds is to look as far in front of your windscreen as possible and not let those little dots become big dots so your evasive action can be minimal, not drastic. It always worked for me. We somedays had to dodge hundreds of big buzzards in multiple flocks by using this technique. I know cockpit workload can make this difficult but getting the busy work done before entering the bird infested area can give you more time to see and avoid them. My neighbor was killed in his F16 hitting a turkey buzzard at 500 ft at high speed when it hit his canopy and knocked him out.

[Machinbird]

I think the best way to avoid birds is to look as far in front of your windscreen as possible and not let those little dots become big dots so your evasive action can be minimal, not drastic.

Another see and avoid advocate. :ok:
Perhaps this is the best reason to be hand flying your aircraft down low in VFR conditions, and not letting "Iron Mike" do it. You need all the response time you can get.

[Green Guard]

Exactly
Plus
many of us tend to forget to use
some of the most important instruments in cockpit
i.e. the cockpit windows

of course if we are VFR

PS
most birds fly VFR only

:sad:

[Pugilistic Animus]

Generally 45 degrees is the accepted stall protection bank angle limit....remeber this; it may just be safer in certain cases to just hit the birds...:\

r2OIxo00UeM

just to add

Sevenstrokeroll =boom shaka laka laka....:)

[misd-agin]

Wings level, close your eyes, and pray(or hope for the non-religious). ;)

Flown by, or through, hundreds, if not thousands of birds during a 30+ yr career. Total hits probably still in the single digits. Amount of manueverings, except for slight pitch changes, to avoid said birds? Zero.

CCS/SVMI Caracas, Venezuela has lots of big birds. You can see them. If you want to avoid them completely you have to land somewhere else. Otherwise you just plow through them and things seem to work out. Apparently the birds read Charles Darwin. :ok:

[Green Guard]

Animus

boom shaka laka laka....

does not belong here. That one made heading change more then 180 deg

people here were talking of just few seconds bank up to 45 or 60
without changing heading more then ~5 deg left or right.

[Pugilistic Animus]

still a very bad idea....very bad:\

[bubbers44]

I can't imagine a pilot losing control of his aircraft dodging a bird. Most of my encounters were below 3,000 ft AFL and in a turkey vulture infested valley. I am sure if I had just flown through them I would have had many engine failures as had many of our management pilots. They were check airmen and doing a lot of inside the cockpit instructing so were distracted. Any pilot that flies through a flock of big buzzards thinking luck will be with him and not bother to avoid them will be in for a big surprise and a grounded airplane. Hope luck is on your side. Avoidance really isn't that hard. I have been below 1,000 ft on final fully configured with a buzzard in my path so avoided him first and then decided if I could still land or had to go around. Sully probably never saw the geese or he wouldn't have made history.

[bubbers44]

Most encounters with the buzzards were above 160 knots entering downwind and with hundreds of arrivals never hit a bird by avoiding them. Pilots who think you can't avoid them aren't looking out the window.

[misd-agin]

When I say 'plow through them' I'm not talking about an identified flock of birds that when seen early enough is avoidable.

So there's the balance, sometimes you can see them and generate seperation by slight flight path adjustments. Other times, IMO the vast majority, it's plow through the random scatterings of birds.

How many engine failures did CKA have going into TGU?

[bubbers44]

I don't know because I haven't done it in over 7 years. One time it was a bird ingestion that grounded the airplane for a day or two to get a mechanic to borescope and check for blade damage. One time it was a bird that hit the leading edge of the wing sticking there and the leading edge slats were damaged retracting the flaps. No engine was shut down to my knowledge because if possible that required a diversion. Both of these events took the plane out of service and both were flown by check pilots. One day on short final I came really close to a bird so opened up the cockpit window to verify we hadn't hit it before retracting the flaps. I don't blame them for what happened because they are busy checking out pilots and are distracted while doing their check pilot duties. I wouldn't want their job at that airport.

[BARKINGMAD]

1. Old RAF saying, "birds always break down" in the effort to gain energy and avoid the big metal bird they are about to ingest, so don't follow them?!

2. Many moons ago the RAF Dominie (Bae 125 bizjet flying classroom) Flight Safety Officer noticed most of that Sqn's birdstrikes were in the aerodrome circuit pattern at 180 kts and below, though the training task required much low flying at 500' MSD at up to 240 kts in the low flying areas of UK and abroad. The difference he attributed to the SOP use of the very bright landing lights in the low flying areas to avoid ingesting Bucanneers, Jaguars, Hawks, Jet Provosts and the like.

3. The SOP for circuit/landing use only prescribed the taxi lights for conspicuity, so the FSO worked hard to persuade the Standards and Training Flight instructors to trial SOP with bright landing lights for circuit and landing use. Having overcome the "not invented here" syndrome, the procedure was trialled and resulted in a REDUCTION IN STRIKE RATE. The complaint that the use of the lights consumed expensive filaments and if forgotten after landing they melting the leading edge perspex cover was treated with the contempt it deserved.

4. The B73NG weather radar radhaz distance for humans is quoted as 15 metres so I very much doubt it is irritating our feathered friends at this range and beyond, though you should be performing a confidence check on taxy out anyway, so might as well leave it on........? The old high radiation power BAC111 "Orange Porridge" weather radars may have been more like poultry microwavers and therefore effective but I have yet to read definitive research on the topic.

5. Too many flying hours and years later my own strike rate is luckily low from following the bright lights policy, deciding I will NEVER duck (no pun intended!) below the approaching flock, and should the multiple encounter with strikes occur my intention is to put the aircraft on the ground ASAP and not to hope that the damaged engines will continue to perform during a go-around.

6. Can anyone supply a link to the RYR B738 accident report at Rome Ciampino for our further education?

7. The 60 deg AOB manoeuvre was a joke wasn't it, just to wind us all up and very effective too............!!!??? :)

[Green Guard]

6. Can anyone supply a link to the RYR B738 accident report at Rome Ciampino

Report: Ryanair B738 at Rome on Sep 7th 2005, loss of situational awareness and terrain clearance (http://avherald.com/h?article=41a5f274)

[BARKINGMAD]

Thank you for the RYR Ciampino link, but I was hoping to read the report on the RYR multiple birdstrike at Ciampino, where I gather the crew tried to follow the Eng Failure on Approach as per QRH/FCTM etc advice.

This is only a valid course of action if at least ONE of the TWO engines responds to a required thrust demand-apparently both of theirs had quit.

The Prune thread at the time shows a photo of an airframe which may never fly again, more importantly everyone walked away or was assisted so to do!

In a year where 3 twin engined aircraft suffered powerplant failure close to the ground, I had hoped those eggspurts who tell us the best way of flying our aircraft could have shown more urgency in researching/revising & publishing the latest recommendations to the pilot community before the next event occurs, as it inevitably will?

There is no reason to suppose the report is locked away in MO'Ls safe as it appears the crew did a magnificent job on the day, or maybe it's because he doesn't want piloting skills to be praised after his widely published comments on our fraternity?????:D

[ATCFloripa]

Imagine an engine mounted a bit lower than the one at the empennage of a MD-11, only with the intake assembled low as in the F-16 featuring a material that would allow a bird to pass through in case of a "nose up" attitude...the fuselage itself would protect the engine intake. It is possible to imagine a thin grid in front of the rear engines which woud trigger some device to deflect a bird away from the engine intake too. As fast as an air bag.

By the way, is there any register of a bird ingestion / bird strike during the night? I guess flying at night offers far less chances to find birds ahead.

I had no idea that birds could feel the RADAR, that's very interesting.

[ChristiaanJ]

By the way, is there any register of a bird ingestion / bird strike during the night? I guess flying at night offers far less chances to find birds ahead.Various bird species migrate in flocks at night, so even if the risk is seasonal, it's certainly there.

I had no idea that birds could feel the RADAR, that's very interesting.I think you'll find that's just an urban legend.....

CJ

[Canuckbirdstrike]

Analysis of data shows that the bird strike rate is higher at night than during the day.

And once again, I can confirm it is an urban legend that aircraft weather radar systems can be detected by birds.