What happens when an F-16 RAF Hawk CT155202 engine sucks in a bird momentarily after takeoff? If this video is any indication, you level off, attempt to restart the engine, fail, point it at an unpopulated area, and eject.
Roughly 5-6 seconds into the video, you can see the bird just before it enters the engine. (Interesting tidbit: if you know the "block number" of the plane, you can figure out if it has a General Electric or Pratt & Whitney engine.)
Those of you paying attention will notice two surprisingly calm voices on the recording. This is a two-seat model (F-16B) rather than the standard single seater.
Posted by jzawodn at March 06, 2006 07:35 PM
Amazing clip! It's remarkable how quickly the pilot reacts to the strike. It takes him a split second to realize it and start pitching up. I assume he's aiming for best glide speed, and, in the process, trading off the excess speed for a bit of extra altitude.
Yeah, get all the altitude you can and use the time it give you to fix the problem or get out safely.
Training matters, huh?
Great video, but not an F-16 ... big clue to me when I first saw this claim a while back is the bird strike appears pretty far off-center, and an F-16 has a single centerline intake (albiet pretty wide), so that didn't seem right.
Here's a definitive writeup that goes into a LOT more detail from people a lot smarter than me about this stuff - it was a CT-155 Hawk - http://www.flightglobal.com/Articles/2006/02/01/Navigation/192/204464/VIDEO+NFTC+CT-155+Hawk+pilots+eject+after+bird+strike.html
VERY professional pilots who remained incredibly calm.
BTW, making a 180 back and get lined up is a LOTTA work in a low energy state - if there is anything straight ahead to put down on, consider that - also minimizes your changes of a stall while turning.
Then again, these guys had an option most people don't, which is pull the handles.
There are a lot of really scary military helicopter crashes on Google Video and YouTube. After seeing them, I have decided that I really don't ever want to fly in a helicopter. It seems like they can go off axis and just go down. I saw one just get swallowed into the ocean while trying to land on a carrier.
I have the same video on my site..
http://www.patricksaviation.com/videos.php?action=view&id=287
It is indeed an RAF Hawk CT155202, and in this case it's being flown by a student, with the instructor in the back. I bet that was a fun training ride.
The video ben refers to is a sea knight fouling a lifeline and pitching upside down into the ocean..
http://www.patricksaviation.com/videos.php?action=view&id=170
"Yeah, get all the altitude you can..." You have a way of getting altitude without an engine? In what you fly? ;-)
Get your airspeed to best glide (which might win you a *little* altitude)... figure out where you're going... then start trying to solve the mechanical problem.
Nick
That was fun.
I'm guessing the number on the upper left corner of the HUD is the airspeed in knots, which would indicate they struck at 225 knots, pulled up to about 125 knots (which should get them over 1,000 ft of altitude, I couldn't locate altitude on the HUD), then managed to turn it around 150 degrees before ejecting. They would have been offset too far from the runway by that point even though they almost had 180.
Why doesn't this happen more often? Is it just "unlikely" that birds will intersect with intake or do they tend to stay away from runways due to noise and such?
F-16 have one engine only with airflow inlet at the center of the airplane body, so it doesn't matter if the bird flew into the left or right side.
I blogged the same video a while back. It is a single engine British Hawk trainer. Note that the airplane speaks with a British accent, and also note that the HUD display is pretty simple compared to that of an F-16.
As a glider pilot, you might appreciate this HUD video of an F-16 that has suddenly become a glider:
http://www.cnn.com/US/9606/29/spectacular.landing/f16pilot.mov
The Hawk has two inlets for a single engine so the bird wrecking it after entering the left inlet doesn't leave a second engine available.
"Why doesn't this happen more often? Is it just "unlikely" that birds will intersect with intake or do they tend to stay away from runways due to noise and such?"
It's rare mostly just because the sky is very big compared with the number of birds. However, some airports have more problems than others. Some of the automated information systems that brief pilots of current conditions at certain airports (Palo Alto, for example, where final is often over the duck pond) always include a warning about bird activity. Engines and windshields for larger planes are tested for bird strikes... by firing frozen turkeys out of cannons. ("What's your job?" "I shoot frozen turkeys at windshields.") Jet engines are designed and tested to take a turkey without failing in a way that would make the airplane uncontrollable.
Unfortunately, birds, like people, get used to noise. Airports have tried all sorts of things to discourage them, with little success... like golf courses that become infested with geese and their leavings... it's hard to find anything that will discourage them.
One thing I learned flying with a friend who's now a USAir pilot -- birds generally will dive when they see a plane headed toward them. Thus, climbing (or descending less) will often prevent the strike... if you have time to react. I learned this on short final to Allegheny County Airport many years ago... and that's the worst time for it to happen, since you're already close to your minimum controllable airspeed and you just don't want to be pulling back on the yoke at that point. My friend JC had the plane at full power and leveled off incredibly fast.
Nick
["Yeah, get all the altitude you can..." You have a way of getting altitude without an engine? In what you fly? ;-)]
I'm guessing an aircraft with forward momentum and wings.
The official accident report (http://www.airforce.forces.gc.ca/dfs/docs/Fti/CT155202_e.asp) even says:
"The IP traded airspeed for altitude..."
It's a British HAWK trainer, not F16. Read the REAL story here...
"I'm guessing an aircraft with forward momentum and wings."
Light planes, the kind Jeremy flies, just won't gain much altitude when the engine is dead, even if they have some airspeed to spare. For one thing, their max airspeed is relatively close to their minimum controllable airspeed, so there's only so much momentum that can be gained. For another, they have fixed-pitched propellors (they can't be feathered), which become effective airbrakes when the engine is dead.
If there's a light plane instructor out there telling his or her students to try to gain altitude after an engine failure, I'd be very surprised and concerned. As far as I know, nobody teaches that. It's airspeed to best glide first, where to land, then the mechanical checklist -- magnetos, fuel tanks, etc.
Fighters are a different beast. Obviously, there's no propellor to slow you down. The difference between MCA and top airspeed is enormous, partly because the way a fighter wins is to be able to fly faster *and* slower than its opponents. (Slower is more important because it allows the fighter to get behind its opponent.)
One of the big killers of pilots with takeoff engine failures is trying to get back to the runway. It's very, very easy to think as if it's a car and you can just turn around and go back... but good instructors beat into their students an awareness of what point it is possible to return to the runway. Otherwise, it's very easy to go into an accelerated stall (not too bad) and then a full stall (very bad at low altitude).
Wouldn't getting airspeed to best glide sometimes involve gaining altitude? I haven't flown in a while but I think best glide speed on a Cessna 152 was around 60 knots, so if I'm cruising at 100 knots when the engine fails, I'm going to pull back which will reduce my airspeed but also cause me to climb a bit until my airspeed drops to 60, right? I don't know what the best glide speed of a fighter jet is, but I imagine the thing is capable of going much faster than glide speed, allowing the pilot to gain quite a bit of altitude while reducing speed.
>Jet engines are designed and tested to take a turkey >without failing ...
But Nick - so why did they crash? Was this engine failure unusual in that normally it would have restarted after eating the bird?
.. and at the USAF Picnic they serve jet cooked and cut turkey sandwiches to save up for custom toilet cost overruns.
Just wondering.. eventhough alek clarified with the flightglobal link that it is a trainer Hawk rather than a F-16, you have not changed the title and content of the journal entry. Do correct it.
I hit a small bird with the wing of the Duo Discus at Hollister. Not sure what they are but they hang around the end of runway 24. There was a flock of these things and I could see the flock just before one hit so I was watching them. Puff it "vaporized" into a small cloud of blood and feathers and there was a little blood mark on the leading edge. The instant "vaporization" of the bird although small is a reminder of how much energy there is even at late final speeds - kind of scary for those glider hits person on the runway accidents. The glider is going to win.
"Wouldn't getting airspeed to best glide sometimes involve gaining altitude? I haven't flown in a while but I think best glide speed on a Cessna 152 was around 60 knots, so if I'm cruising at 100 knots when the engine fails, I'm going to pull back which will reduce my airspeed but also cause me to climb a bit until my airspeed drops to 60, right?"
Yes, but hardly any. Airspeed drops very, very quickly in light planes without an engine, even if you hold the plane level, much less climb. My point wasn't that you can't gain any altitude, it was that gaining altitude isn't something to even *think* about when the engine fails and is relatively insignificant in light planes (especially when climbing, as was the case in the video). To the extent you gain altitude, great, but to give it any attention, rather than focusing first on airspeed, is a mistake.
">Jet engines are designed and tested to take a turkey >without failing ...
But Nick - so why did they crash?"
You left out the context -- "...in a way that would make the airplane uncontrollable." The idea is that sucking up a bird doesn't cause the engine to disintegrate, explode, etc. I don't think anybody has made a jet engine that will keep providing power, at least for very long, after taking a bird of any significant size. The airplane in the video was still controllable or the pilots would have ejected (or tried to) right away.
Nick
Thx Nick - a very interesting thread of posts here. I'll never view my Thanksgiving bird dinner in quite the same way again.
Wow....I am utterly impressed at the vast knowledge of avaiation here. My philosphy in life is; try and be the best you can at what you do and be prepared and alert for any situation......however, at the end of the day.....if you have an appointment to have a piano fall on your head or what could have been in this instance a bird fly into your engine, your not going to be late for the appointment.
Airspeed to Altitude is very important - why?
It is often said (especially about MU-2s)that "airspeed is insurance, and altitude is life insurance..."
In a military airplane you have an extra option you don't have in a civilian airplane - you can eject.
You can't eject at low altitude (well you can, but survival is better higher), so if you are flying at over 250, or whatever, you trade that for altitude, try to fix the problem (in this case it was an overtemped engine from the formal british warnings) then decide what to do next - ride it down, or eject.
You'd also trade airspeed for altitude if you have an engine failure in any high performance/high speed single engine.
In a twin, you'd maintain heading, pitch for best rate of climb with one engine inoperative (VYSE/blue line)then accept whatever performance you can get with a controllable airplane. (sometimes a descent in light underpowered twins)
Hope this helps, from an ATP & Flight Instructor
Already stated that it was a Hawk and not an F-16. To my knowledge the RAF doesn't fly F-16's at all..anyone confirm?
Nope, RAF do not fly F16, which is a shame, as it is far more capable, and one hell of a lot cheaper than the tornado, which can only go in a straight line.
As for the airspeed/altitude debate, I thought it pretty standard behaviour, even in light aircraft, to convert any excess airspeed/energy into altitude or a better position from which to begin a FLWOP, because even a hundred feet to play with makes a difference.
It was A Canadian Ct-155 from Moosejaw Sask. From the NATO Training School.
Some words from a USAF F-16 and glider pilot. There is some good information here. The HUD video is definitely not from an F-16, but is still interesting. In any sort of engine failure on or after takeoff, and aborting or landing straight ahead is not an option, procedures are to climb (~30 degrees nose high), jettison any stores, and eject as high and slow as possible. The seat is designed to work on the ground at zero airspeed, but the higher the better. You just won't get enough altitude to complete an engine restart and get usable thrust prior to needing to eject. Now, if you are flying tactical airspeeds (500 knots) at low altitude, you can gain several thousand feet of altitude and have a good chance of restating an engine.
With any sort of engine or thrust related problems, procedures dictate to climb straight ahead to 2000 feet before starting any turns. That ensures you are in the best ejection envelope if the need arises. Any turns in a low thrust situation will prevent you from gaining as much altitude as you can.
Fighter mentality is different than flying light aircraft. We don't have the option of landing on a road or smooth field (would most likely destroy the jet and cause personal harm), and we do have an ejection seat. So, the jet is either flyable back to the runway, or we eject.
As for bird strikes. They are a regular occurence from time to time. Rarely do they get ingested an cause engine failure. Almost anything down an engine will cause some damage. It usually takes a large and heavy bird to cause catastrophic engine failure. Once that happens, there isn't much of a chance for a restart. Also, it is true that the best bet is to pull up to avoid birds you see. They normally dive down when surprised by jets.
Hope this helps.
I'm a flight instructor.
In cruise, I advise a private student to hold altitude until the airspeed approaches best glide, then descend at best glide, but I would expect a commercial student to trade some of that airspeed for altitude, while looking for a place to land and completing the engine out emergency checklist.
A light airplane at takeoff has a climb speed very close to best glide (e.g. C152 best rate of climb is 67, best glide is 60), so action in case of an engine failure is to stuff the nose down to maintain airspeed at best glide. The jet however, clearly had some speed to trade, so they did.
Amusingly, before I read the commentary and learned that it was an instructional flight, I thought, "the captain sounds just like a flight instructor." I always try to cut that tone out of my voice when I am captain on a two crew aircraft, not wanting to annoy my FO.
I've got about 1500hrs fast jet, including the Hawk.
In that situation speed increases very quickly on takeoff. You need to cash-in that energy and get the speed back to best glide (where the wing is most efficient) asap. This gives you the most important thing you need at that point, maximum time to relight and the height to attempt a turnback to either the crosswind runway or point towards a suitable ejection area.
Hi, I'm a civil airliner Engineer and may be able to explain the physics of why its better to convert airspeed to altitude.
As airspeed increases so does drag, but drag increases to the square of airspeed, i.e. 100knots will give 100 units of drag but 200knots will give 400 units, so rather than waste the airspeed in drag, its better to convert any spare into altitude (and do it as fast as possible), as this is the most efficient use. And of course the aircraft will lose less energy in drag at a lower airspeed (and to a much lesser degree the air is less dense with increasing altitude so drag is reduced here too), but is now at a safer altitude. This is true for all aircraft, but as has been explained above, the higher the Cd/mass ratio (higher in light aircraft with props), the less safe it is to convert as there is physically less airspeed to convert, so the act of climbing (which will increase the amount of drag lost as the aircraft presents a larger frontal area and the wing gets taken out of its optimal attitude) may out weigh the benefits, i.e. the aircraft loses more energy in trying to save energy, also climbing takes the aircraft to a position it is not stable in (especially with a stationary prop on the nose) and may pitch up beyond the command input of the control surfaces, which as you may imagin is slightly dangerous.
Incidently the Cd/mass ratio of commercial aircraft is the highest of all types of airframe and if all engine power is lost (simply does'nt happen, but is trained for), the pilots should pull full back and gain as much altitude as possible and deploy full flaps when the airspeed allows (it could be immediatly) and keep climbing until close to the envelope of stall, only then do they even look at doing anything else.
Hope this was helpfull, may have been written a bit hard to understand (im not a teacher).
Wow! Very interesting. I thought I saw the GS/AS roll up to 235 knots+? when the bird ame into view and FODed the engine. Anyway; I read where one person wondered why the bird appeared as if it was offset beyond center and how it could be ingested.
I can only add the the HUD is about 4"-6" or so and in relativity to the plane's size, the bird did appear to come left of center but, still would have been ingested as was obvious. That intake is sucking air at a wide angle and very powerful.
I was a jet mech in the Navy and worked on 6 different type aircraft. It's amazing what FOD can do. We even had a "Sand Crab" sucked into a F-86 Sabre Drone that was at High Power for a engine run up, and the poor guy was sucked in at 100% Full Military with the tie-down chain attached. Anyway; he busted his chest open on the engines inlet cone and it killed him although he was not fully ingested into the engine itself like a TF-41 would do on an A-7E Corsair.
The pilots sure did a nice job and was able to maintain 130 +/- knots to get in position before ejection. I imagine they still had take off flaps and such, and did very nice into getting in a safe place to abort.
Anyway; hope they both survived ejection without any major injuries.
yeah i'm a jet engine mechanic as well and i agree. even if the bird was passing on the left, especially at takeoff, there is SO much air being sucked into that intake that it would still bring it into that intake. We recently had an F404 running at full AB at test cell and just standing next to it, closer to the AB than to the fan, i couldn't believe that my coveralls were still being sucked towards the front of the engine!
I don't understand why everything thinks that this is an F-16. Thats not the HUD of the F-16 and the D models are rare enough, let alone to have 2 pilots in it rather than one in the front taking a visitor on an incentive flight. Further, the bird struck off the left side, where the engine would be on an F15 or an F18. Thats not an F-16.
I don't know why everyone commends the pilot. He screwed up and was lucky to survive without hurting anyone on the ground
He pulled up way too steep, zooming right through his best glide speed and ended up almost stalling. Though he gained 1500 feet in the zoom, the low speed and the unnecessary turn p!ssed away most of it, so he was about 700 feet above ground when they ejected.
I have flown off this runway (Rwy 29R, Moose Jaw, SK) thousands of times. On runway heading, he had nothing but 500 miles of wheat fields in front of him. But he turned towards the only inhabited area within 50 miles, the city of Moose Jaw, which is only three miles away. You can see it in the video just before the frame sync loses its hold.
With 20/20 hindsight, the correct action would have been a moderate pullup, maybe 5 degrees nose-up, to establish best glide speed, trim to maintain glide speed, try a relight, then eject straight ahead.
