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RV-4 Turkey Vulture Birdstrike in FL

roadrunner20

Well Known Member
An EAA chapter member of mine had an encounter with a turkey vulture 2 weeks after he purchased this beautiful RV4. Fortunately, He was able to fly it back the 40 miles to his home base in Brooksville, FL (KBKV) after the tower confirmed he still had his gear intact. This is an amazing feat considering the damage incurred. It just goes to show how incredibly strong these aircraft are engineered.
We checked the wing alignment Saturday to insure the spare had not been compromised. It had not.
We'll be able assess in more detail once the wing skin is removed.

http://www.3dsky.us/rv7/images/img_1942.jpg
http://www.3dsky.us/rv7/images/img_1940.jpg
 
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Holy C---

Wow that's amazing... how did the plane fly after that damage?
Just goes to show how little Bernoulli's principle contributes to lift...
 
Impressive damage.. Is anyone aware of a bird strike to the canopy in an RV-4? I see the results often on the military side and know what specifications we put on tactical aircraft windscreens. As my face sits 10" from the fwd windscreen I've been curious to wee what if any testing has been done or what real world encounter is out there and the end result?
 
He's done a **** good job getting it on the ground in one piece, I can't imagine that amount of damage did any good for the aerodynamics of the wing. Though I'd be pi$$ed if that happened to my 2-week-old RV...

One for the American's...What's the ruling for repairs like this? My understanding of our (Australian) Experimental category is the original builder can do "what he likes" but anything else needs to be OK'd by a LAME(A&P). Is that the same that side ofthe Pacific?
 
Impressive damage.. Is anyone aware of a bird strike to the canopy in an RV-4? I see the results often on the military side and know what specifications we put on tactical aircraft windscreens. As my face sits 10" from the fwd windscreen I've been curious to wee what if any testing has been done or what real world encounter is out there and the end result?

As it is made of the same material as the RV-8, and I have had quail come completely through mine, I can say with almost certainty that a bird of this size will (to quote Dirty Harry) "...take your head clean off".
 
holly crapola vanman! it is as i go out flying every day, # one to keep my eyes out side the cockpit for big birds 95% of the time. they can come up on you in a heartbeat. glad he got home safely. dan is a good man to help in the reconstruction. they seem to be more prevalent around late breakfast, the most important meal of the day.

bridstrike.jpg
 
As it is made of the same material as the RV-8, and I have had quail come completely through mine, I can say with almost certainty that a bird of this size will (to quote Dirty Harry) "...take your head clean off".

... And I can tell you from first hand experience that a red tailed hawk (~3lbs) at 120kts will go straight through a RV-7 canopy without any trouble. After shattering the canopy it still had enough energy to bend the steel support tube going up to the roll bar.

RV canopies don't stand a chance against a large bird like a Turkey vulture (~6lbs) or goose (~20lbs).
 
Just goes to show how little people understand physics... :)

Was waiting for someone to bite on that... :D

It's an interesting debate... in reality - depending on the wing of course, Bernoulli's Principle contributes about 10% to the total lift of the wing*. Take a look at the upper surface of the wing in those pictures and it's hard to imagine a clean boundry layer of airflow could exist over the top. Dan hasn't commented yet on how difficult it was to control the airplane after that amount of damage, but the pilot certainly got it safely on the ground. I think we under estimate how much lift is generated from air hitting the underside of the wing producing an upward force. Stick your hand outside the window of a moving car and you can demonstrate this. There are plenty of airplanes with symmetrical wings that fly very well - even upside down. A lot has to do with AOA, but there are many other forces at play too.

I often think of those 25 cent (OK, I'm dating myself) balsa airplanes with the flat wings, and how nicely they fly...

* - This from the Boeing engineer who designed the wing on the 787. Actually his comment to me was "Tom - don't tell anyone, but we really have NO idea how a wing flys..."
 
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I've had more near misses with vultures the past couple of weeks than I can ever remember. Sobering photos.......................
 
Impressive damage.. Is anyone aware of a bird strike to the canopy in an RV-4?

Not great results!

Couple of threads on the forum about Birds Strikes on RV-8 plexy. A bird strike on any canopy would spoil your day, and one of the reasons why the Military wear head gear!

CockpitView.jpg


It?s the only time Dick Dasterdly wouldn?t want to catch a pigeon !

stoppigeon.jpg
 
Your friend has balls of steel. I would've landed that sucker right away. If that wing hit a critical angle, she could've stalled.
 
Test the stall.

Guys, I've ferried quite a few ag airplanes that had hit tree limbs and big birds with a huge amount of damage. It's a dangerous condition when it happens to you in the air.

Please, before you make your approach, take her up and see where it stalls at altitude. I'd bet that RV-4 had to land at least 10 MPH faster. Making a normal approach with this much damage could snap you over when you least expect it.

Best,
 
Please, before you make your approach, take her up and see where it stalls at altitude. I'd bet that RV-4 had to land at least 10 MPH faster. Making a normal approach with this much damage could snap you over when you least expect it.

This is a great comment and one that, obviously, comes from experience. Sometimes, the overwhelming desire to 'get her on the ground' can be blinding. Similar to tailrotor issues in a helicopter - yes you desperately want to be on the ground, but taking the time to evaluate control authority at various approach speeds can make the difference between a pucker factor landing, bent metal, or worse....
 
Pierre has excellent advice. When you have aerodynamic problems or damage you need to make a control check at a safe altitude. Your really looking only for a safe speed to land. You don't want to see how slow a damaged aircraft can fly at. You want to pick a speed well above normal based on the degree of possible damage and establish the aircraft will fly at that speed and not go below it on a approach.

George
 
Stalls????

I'll bet you stalling an airplane with that kind of wing damage could be VERY exciting... Be sure your spin avoidance/recovery techniques are up to snuff :eek:
 
Impressive damage.. Is anyone aware of a bird strike to the canopy in an RV-4?

A few years ago I was flying along under a low overcast at about 1,500' AGL heading south of my airport to where the weather was much better and I planned to climb to cruising altitude for a trip to SC. You could say it was scud running but I was intimately familiar with the terrain and route on the corridor I was flying and had good evidence from radar and satellite imagery that the good weather was about 20 miles away. Nevertheless the pucker factor was higher and the level of attention I was paying to what I was doing was elevated given the circumstances. About that time I saw a flash headed toward me and then a very loud "BANG" sound. I flinched instinctively as a bird stuck my RV-4 canopy dead center in front of my face. In short it scared the S*** out of me.

After what seemed like quite some time but was in fact a few seconds I realized all was well, the canopy did not even crack even as blood and guts remained smeared on the canopy.

I don't know what type of bird it was as their was not enough evidence left to suggest once I landed in SC (yes I completed the trip). Based on the very instantaneous glance I got of it before impact I would hazard a guess it a small to medium size songbird or perhaps a starling size bird. Because the RV-4 canopy flows back so much at the front I'm thinking the impact was of a glancing blow sort even if, based on the goo left behind, I"d say the impact was about 2-3" above the bottom of the glass.

So not a scientific test by any means but at least in this case the canopy survived. I often wonder what would have happened had it been a larger bird and had somehow incapacitated me at low altitude. Not a comforting thought. I had no warning and zero reaction time. One minute droning along and then....

Richard Bibb
RV-4 N144KT
 
CONTROLLABILITY CHECK

To add to Pierre's comment, consider a controllability check (shamelessly borrowed from military manuals):

Collision & Structural Damage:

Maintain flight within limitations for aircraft configuration (flap, gear etc) - do not change configuration, conduct controllability check.

Controllability Check:

Attain a minimum of 3000ft AGL.

Determine minimum control speed, ie, reduce speed slowly until first detection of:

Control Impairment; or

Airframe buffet; or

Half control deflection needed for straight & level flight.

Recover to nearest suitable airfield maintaining a minimum of 10KIAS above minimum control speed, and use 10KIAS above minimum control speed as the landing threshold speed.

Regards
 
FWIW

I don't wear a helmet, but I -always- wear ANSI Z-87 safety glasses...they come in clear and tinted, and they're cheap...
 
Wow that's amazing... how did the plane fly after that damage?
Just goes to show how little Bernoulli's principle contributes to lift...

He said it handled a bit mushy at low speeds which is to be considered. He tested some slow flight at higher agl prior to committing to landing. He did land hot.

The forward skin was removed today and the wing looks salvagable with only the need to replace the skin, ribs and addition of some new spar stiffeners to the area. The spar was lightly stressed just outboard of the original stiffener. I'll update the thread as conditions move forward.


BTW, sorry about the image size. I'll have to take a look at the image tutorial prior to uploading.
 
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Bird Strikes

On Nov 23, 1962 a United Airlines Vickers Vicount was struck in the horizontal tail by a flock of whistling swans. The entire tail separated from the aircraft and the aircraft crashed.
The Lear 23 does not have a bird proof windshield. Most small jets have bird proof windshields. On July 4, 1981 a Loon came thru the windshield of a Lear 23 and killed the pilot. I had always heard that the captain was killed. The article that I found says that the copilot was killed. The aircraft was landed safely.
I have seen pictures of a Convair 580 where a bird came thru the pilots windshield with such force that it struck and badly damaged the electrical panel behind the pilot. I have never been able to find additional details about this accident.
There are literally dozens of accidents worldwide reulting from birdstrikes, many of them fatal.
Several of the fatal accidents were the result of failure to properly fly the airplane after engine failures caused by bird injestion.
 
Thanks for the photos on canopy encounters and it confirmed my expectation on strength or lack there of in the speedy RV. I've flown with a ton of turkey vultures, red tail hawks and bald eagles in my sailplane, just make a note that the defensive maneuver for the vultures is to fold up there wings with the obvious flight dynamics outcome. So avoid flying under them as they are easily spooked and fold up their wings, so if you are lucky enough to see them pull to go over vice under them. Red tails and eagles rarely are spooked and they will thermal with you sometimes flying just above you. Regardless, if you have the chance go over no under. Where are they likely found? Upwind side of cumulus clouds and under, so if you fly above the convective clouds which is my preference in the RV for a smooth ride then no worries. Below, avoid flying under the cu's and you will lower your probability of an encounter.
 
Fortunately, He was able to fly it back the 40 miles to his home base in Brooksville, FL (KBKV) after the tower confirmed he still had his gear intact. This is an amazing feat considering the damage incurred. It just goes to show how incredibly strong these aircraft are engineered.

Does no one else see anything wrong with this? Looking out at the wing and having the tower confirm gear are still there, then fly 40 miles to home base? Could they tell there was no spar damage from inside the plane and from a tower flyby? He sounds like he was luck twice.
If I had a bird strike with any damage, I would land at nearest airport and inspect.
 
Does no one else see anything wrong with this? Looking out at the wing and having the tower confirm gear are still there, then fly 40 miles to home base? Could they tell there was no spar damage from inside the plane and from a tower flyby? He sounds like he was luck twice.
If I had a bird strike with any damage, I would land at nearest airport and inspect.

He flew 40 miles TO his home base for the tower flyby.
This was his only towered option other than take the chance the gear was not compromised. Since he deemed the aircraft was controllable, he elected to fly home versus an off field landing.
 
One quick thought (also based on past military procedures): The problem with this procedures is that, depending on the damage, you may lose control before achieving any of the indications noted. Not so bad if you have an ejection seat, but otherwise not what we want to happen. I suggest that you follow this procedure until you reach a safe landing speed (90 KIAS?). If you get to that speed without any of the below indications, maintain above and land at that speed. If you get the indications at a higher speed, follow the procedure and make the best landing of your life.

-John

To add to Pierre's comment, consider a controllability check (shamelessly borrowed from military manuals):

Collision & Structural Damage:

Maintain flight within limitations for aircraft configuration (flap, gear etc) - do not change configuration, conduct controllability check.

Controllability Check:

Attain a minimum of 3000ft AGL.

Determine minimum control speed, ie, reduce speed slowly until first detection of:

Control Impairment; or

Airframe buffet; or

Half control deflection needed for straight & level flight.

Recover to nearest suitable airfield maintaining a minimum of 10KIAS above minimum control speed, and use 10KIAS above minimum control speed as the landing threshold speed.

Regards
 
The Lear 23 does not have a bird proof windshield. Most small jets have bird proof windshields. On July 4, 1981 a Loon came thru the windshield of a Lear 23 and killed the pilot. I had always heard that the captain was killed. The article that I found says that the copilot was killed. The aircraft was landed safely.

I was a friend of the co-pilot that was killed in that incident. As I recall, it happened at night, departing Willow Run (or perhaps another Detroit area airport) on an auto parts freight flight. The co-pilot was a young A&P who had worked hard to get his pilot ratings and had managed to get his first jet flying job. I remember hearing that the captain had a pretty scary time getting the airplane back on the ground at night, with no windscreen, and the horrible situation in the cockpit.
Sad memories for me.
 
Good Question...

...but how are you going to protect your face?

Good luck,

I vividly recall an incident when I was a kid of about 10 years of age (so year about 1954). I was with my Dad; and we were close to a vehicle that hit a buzzard and it went through the windshield and killed one of the occupants. I cannot recall if it was the driver or passenger or exact details; but the victim's head was a bloody mess. I don't know if from glass or impact.

However, I just guess the vehicle speed to be no greater than 70mph. I'm wondering about the helmet protection?? Thinking one has to play the odds in something like this. Turning the head slightly would involve more helmet. Guessing better to have the helmet than to NOT??? :confused:

Yes, Good luck to us all!!!
 
Lear

The Lear accident occurred just after takeoff at Cincinnatti Lunken airport. Intended destination was Detroit. Right engine also failed from injesting windshield and upholstery material.
 
I guess I'll wear safety glasses and the visor.. I would rather a bloody face then a head injury or head trauma..
 
Painting spinner

A question for those who have real world experience in this, does painting a section of the spinner a different colour really work in scaring off birds (strobe effect) or is this just hanger talk??

Clive Whittfield
Auckland
New Zealand
 
My RV is bright yellow. Maybe that will be a good deterrant?:eek:
I went to the same location of the strike on Saturday to get fuel. I found myself cautiously scanning for the buggers.
 
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My RV is bright yellow. Maybe that will be a good deterrant?:eek:
I went to the same location of the strike on Saturday to get fuel. I found myself cautiously scanning for the buggers.

The bright yellow is as good as any IMO. I believe it is safe to say "birds" have vision that is far superior to we humans. I think they see us... I've been dodging the buggers for some 40 years now.

Your cautious scan Dan, is probably our most effective tool. I'm afraid the duty to avoid falls on us. :(
 
I wonder sometimes if certain combinations are more prone to birdstrikes, as the critters seem to be drawn to me like a magnet. Aside from the half dozen quail I took out at once, I have had at least 4 other confirmed incidents in this airplane - all inside of 150 hours.
 
I wonder sometimes if certain combinations are more prone to birdstrikes, as the critters seem to be drawn to me like a magnet. Aside from the half dozen quail I took out at once, I have had at least 4 other confirmed incidents in this airplane - all inside of 150 hours.

May I ask what color is your RV?
My friends was white with blue stripes.
 
An EAA chapter member of mine had an encounter with a turkey vulture 2 weeks after he purchased this beautiful RV4. Fortunately, He was able to fly it back the 40 miles to his home base in Brooksville, FL (KBKV) after the tower confirmed he still had his gear intact. This is an amazing feat considering the damage incurred. It just goes to show how incredibly strong these aircraft are engineered.
We checked the wing alignment Saturday to insure the spare had not been compromised. It had not.
We'll be able assess in more detail once the wing skin is removed.

http://www.3dsky.us/rv7/images/img_1942.jpg
http://www.3dsky.us/rv7/images/img_1940.jpg

Great news!
Bruce flew his RV4 post birdstrike, for the first time today.
She was sporting a brand new paint job & paint scheme.
He said she flew "flawlessly".

img_6787.jpeg
 
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Beautiful repair job

Wow, she looks great. Super repair and paint job.

Out of interest, I went and looked up Turkey vulture information. Wikipedia (it must be right!) lists the mass as 0.8-2.3 kg. A believable RV speed is 160 kts, (82 m/s).

Using good old 1/2mV^2, the energy of the strike is 2700-7700 Joules. The upper end of this is getting dangerously close to the 10 kJ kill criteria (10 kJ imparted to mechanical system kills most anything). If it came through a canopy and hit you I don't know if a helmet would help or not.

cheers

G
 
Ironic. I hit a turkey buzzard in a Mooney about 15 years ago in FL, same spot on the wing with similar damage. I think we were indicating about 145 knots.

Airplane was flying fine at 145, kept it there. Flew a long final (to a 12K' runway)... slowed to gear speed at 3K feet so we'd have enough to push over and regain airspeed, dropped the gear, and kept it at gear speed until about 2-3' off the runway, let the airplane settle when it was ready.

We discussed doing a controllability check but the potential loss of control and recoverability was our main concern and we had a long enough runway available to just land fast.

Considerations....
 
Ironic. I hit a turkey buzzard in a Mooney about 15 years ago in FL, same spot on the wing with similar damage. I think we were indicating about 145 knots.
.

At that speed, the buggers come up on you very fast.
We've learned to take evasive action using a quick stick pull up, as they tend to dive when they see you.
 
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