Les / Creative Edge Photo Posted August 31, 2011 Share Posted August 31, 2011 Hey, catching Top Gun on AMC, features notes during the movie but a few questions on the F-14 notably the Flat spin and ejection. First, they noted in the movie notes the incident that caused Goose's death was a result of the flat spin causing a low pressure zone on the ejecting canopy. Is this sort of even really possible in a flat spin? Next, would not the top of Goose's ejection seat have hit the canopy and offer some protective zone? I know the G's of hitting the canopy from an ejection would likely be high but would engineers not have factored in this sort of stuff in designing the jets? One more thing I know F-14A with the TF-30's had an issue with stalling out from especially higher AoA. Did the uprated GE's in the later B/D versions suffer similar issues. I know lots of F-14 fans here any help in answering my questions will be appreciated. :) Quote Link to post Share on other sites
Wayne S Posted August 31, 2011 Share Posted August 31, 2011 Hey, catching Top Gun on AMC, features notes during the movie but a few questions on the F-14 notably the Flat spin and ejection. First, they noted in the movie notes the incident that caused Goose's death was a result of the flat spin causing a low pressure zone on the ejecting canopy. Is this sort of even really possible in a flat spin? Next, would not the top of Goose's ejection seat have hit the canopy and offer some protective zone? I know the G's of hitting the canopy from an ejection would likely be high but would engineers not have factored in this sort of stuff in designing the jets? In which way are you looking at Gs? Frankly, dieing from a brain injury, only thing that matters is, how hard the brain impacts the skull, in essence the skull does not need to come in contact with anything. The brain only needs to have enough acceleration to impact the skull itself. Quote Link to post Share on other sites
Mumbles Posted August 31, 2011 Share Posted August 31, 2011 (edited) As I understand it from a couple of sources, and also based on the advisor commentary on the DVD, Goose's death was based on an actual incident. In a fully developed flat spin the aircraft would be falling rather than flying; I can see how the canopy would linger close to the aircraft if both were more or less in free fall with little to no lateral movement. Edited August 31, 2011 by Mumbles Quote Link to post Share on other sites
catfan Posted August 31, 2011 Share Posted August 31, 2011 i always thought the heat from the other jet caused the engines to have a compresior stall wich caused the spin. to any body out there am i right? Quote Link to post Share on other sites
Jinro Posted August 31, 2011 Share Posted August 31, 2011 In the ejection scene, it appears that Goose's head actually impacts the canopy. I was under the impression that the ejection seat is always taller than the pilot's sitting height (unless you had a really tall pilot which probably isn't allowed). I thought that if that happened in reality, the top of the ejection seat would just smash through the canopy. Quote Link to post Share on other sites
Mumbles Posted August 31, 2011 Share Posted August 31, 2011 i always thought the heat from the other jet caused the engines to have a compresior stall wich caused the spin. to any body out there am i right? Jetwash/exhaust rather than heat disrupting the airflow into the intake. The intake/airframe/engine marriage on the F-14A was by most accounts a less than a happy one. Quote Link to post Share on other sites
Mumbles Posted August 31, 2011 Share Posted August 31, 2011 In the ejection scene, it appears that Goose's head actually impacts the canopy. I was under the impression that the ejection seat is always taller than the pilot's sitting height (unless you had a really tall pilot which probably isn't allowed). I thought that if that happened in reality, the top of the ejection seat would just smash through the canopy. I'd say definitely if the canopy were still attached (and restrained) to the airframe, but free floating I'm not so sure. I'm not an expert at all, I'm just going from things I have seen and read. Quote Link to post Share on other sites
Pete Beck Posted August 31, 2011 Share Posted August 31, 2011 It's well documented that the TF-30 engine installed in the F-14A was prone to compressor stalls due to the disruption of airflow at the intake. This caused the flameout of one engine while the opposite continued thrust inducing a spin. It was also susceptable to severe throttle changes and the pilot had to use extreme care on throttle settings during high g maneuvering. A digital engine control was eventually fitted to the A model but it didn't completely alleviate the problem and there were several flight restrictions that remained until retirement. The F-110 was very forgiving of airflow disruptions and the spin was not an issue. There were no throttle restrictions either. Quote Link to post Share on other sites
Finn Posted August 31, 2011 Share Posted August 31, 2011 Long time ago i saw a video of a F-14 on a test flight go into a flat spin, a chase a/c was following their descent informing the crew of their height. As they passed a certain altitude, and still in a spin, he told them to eject and when they did, the canopy just rolled over to the side. The crew got out okay. Jari Quote Link to post Share on other sites
Jennings Posted August 31, 2011 Share Posted August 31, 2011 Yeah, even in a flat spin that canopy's got enough mass that it's going to go somewhere if you fire the explosive bolts. It wouldn't just float there, and even if it did, a rocket powered ejection seat is gonna push it out of the way. Quote Link to post Share on other sites
doupnik Posted August 31, 2011 Share Posted August 31, 2011 IIRC, on one of the DVD extras, one of the F-14 pilots who was a technical advisor had input on the crash. Something about it had happened to an actual RIO. mason Quote Link to post Share on other sites
Scott R Wilson Posted August 31, 2011 Share Posted August 31, 2011 One of the many dumb lines in the move: "He's in a flat spin! He's headed out to sea!" Huh?!?? Let's see, flat spin, falling straight down while rotating, yet heading out to sea... just doesn't compute. FWIW, during my time at Ramstein 1983-86 we had just one F-4E crash. It was during a WSEP deployment to Tyndall, a 526 TFS jet (68-0535) being flown by a 512th TFS crew had a midair with a Tyndall F-15. The F-15 jock and both F-4 crewmembers ejected, but one of the F-4 crewmembers hit his canopy during the ejection sequence and was injured bad enough that when he landed in the Gulf of Mexico he was still unconscious and drowned. Very sad as his family had all flown to Florida to meet him and do some touring the local area with him, but never even got to see him before this happened. I don't know if the Phantom was in a flat spin, but I'm just sayin' stuff like this can really happen. Scott Wilson Quote Link to post Share on other sites
Les / Creative Edge Photo Posted August 31, 2011 Author Share Posted August 31, 2011 In which way are you looking at Gs? Frankly, dieing from a brain injury, only thing that matters is, how hard the brain impacts the skull, in essence the skull does not need to come in contact with anything. The brain only needs to have enough acceleration to impact the skull itself. I agree injuries to the brain inside the skull can be deadly. But I wonder what kind of g's would be entailed as such in the movie. Quote Link to post Share on other sites
Les / Creative Edge Photo Posted August 31, 2011 Author Share Posted August 31, 2011 One of the many dumb lines in the move: "He's in a flat spin! He's headed out to sea!" Huh?!?? Let's see, flat spin, falling straight down while rotating, yet heading out to sea... just doesn't compute. FWIW, during my time at Ramstein 1983-86 we had just one F-4E crash. It was during a WSEP deployment to Tyndall, a 526 TFS jet (68-0535) being flown by a 512th TFS crew had a midair with a Tyndall F-15. The F-15 jock and both F-4 crewmembers ejected, but one of the F-4 crewmembers hit his canopy during the ejection sequence and was injured bad enough that when he landed in the Gulf of Mexico he was still unconscious and drowned. Very sad as his family had all flown to Florida to meet him and do some touring the local area with him, but never even got to see him before this happened. I don't know if the Phantom was in a flat spin, but I'm just sayin' stuff like this can really happen. Scott Wilson Interesting story, sad too. I guess if it can happen it will happen. I bet though such an incident is very very rare. Quote Link to post Share on other sites
Les / Creative Edge Photo Posted August 31, 2011 Author Share Posted August 31, 2011 More from the movie "notes" They said in notes during the final air to air combat scenes that the US Navy does not have too many combat planes :D yes maybe compared to the USAF and maybe to air power in China and Russia. But the USN has more combat planes than most other countries have aircraft in their entire air forces. Anyways they noted because of that often for comparison where the USAF may send say 20 aircraft into combat the USN may only send in 4. Really is it that much of a difference? Quote Link to post Share on other sites
spike7451 Posted August 31, 2011 Share Posted August 31, 2011 In the ejection scene, it appears that Goose's head actually impacts the canopy. I was under the impression that the ejection seat is always taller than the pilot's sitting height (unless you had a really tall pilot which probably isn't allowed). I thought that if that happened in reality, the top of the ejection seat would just smash through the canopy. They do,a lot of seats,especially the older types have what we call canopy breaker horns on the headbox & also by the knee area.These are designed to punch thru the canopy in the event the MDC fails to fire.On some two seat aircraft you'll see that the rear seat differs from the front seat in the size of the breakers,which is mainly due to the angle of the canopy.The seat pan is motorized to the crew can adjust the height of the seat back to get proper positioning of the straps ect. The seats are also ever so slightly off set by one or two degrees.Not so much as you'd notice visually but enough to stop the seats colliding on ejection. Quote Link to post Share on other sites
Murph Posted August 31, 2011 Share Posted August 31, 2011 Hey, catching Top Gun on AMC, features notes during the movie but a few questions on the F-14 notably the Flat spin and ejection. First, they noted in the movie notes the incident that caused Goose's death was a result of the flat spin causing a low pressure zone on the ejecting canopy. Is this sort of even really possible in a flat spin? Yes. I know an individual who had exactly that happen in an F-15. The fact he survived was nothing short of a miracle; although, he's had all sorts of problems since, like waking up out of a coma and looking at his wife and asking who she was. He pretty much had to relearn everything about his previous life. Regards, Murph Quote Link to post Share on other sites
Mumbles Posted August 31, 2011 Share Posted August 31, 2011 Did a bit of google-fu on this topic this afternoon, and it is supposed to have happened to an F-14 crew c.1979. The incident apparently resulted in a modification to both the physical ejection sequence and SOP/NATOPS for ejection from an out of control F-14. Another factor to apparently consider in this situation is centripetal force on the crew, as they are spinning around the aircraft centrepoint, to the tune of 4+G. If someone with genuine knowledge could confirm the details (besides the confirmation on the DVD that it did in fact happen) that would be cool. From what I have gathered so far: F-14 flameout inducing flat spin totally feasible. Maverick being unable to reach ejection handle due to centripetal force totally feasible. Canopy not clearing sufficiently for safe ejection totally feasible. Quote Link to post Share on other sites
Jay Chladek Posted August 31, 2011 Share Posted August 31, 2011 The main reason why the canopy didn't clear in a flat spin is because it is designed to blow up and away to clear the ejection seat paths when the airplane is normally going forward. But in a flat spin, it would just end up spinning upwards in the center of the spin and would make a target that could be hit by the RIO. Yes, according to the talk given by the F-14 driver at IPMS Nationals at Omaha (who was in VF-84 and later an instructor at Top Gun) an actual incident did happen at Point Mugu in the 70s and from what he remembers, the RIO did die. Also, to my knowledge, F-14 ejection seats do not have cutters mounted on the top of the seat. So they aren't designed to shatter a canopy like say an A-6 ejection seat. Canopy plexi-glass is pretty tough stuff and that leaves three methods of dealing with it: get rid of it, cut it, or use det cord to shatter it (such as in a Harrier or a Hawk). As such, canopy jettison is an integral part of the ejection sequence from an F-14. Could impact with a canopy kill somebody with a head injury? Well, could a foam piece falling from the external tank of a space shuttle punch a hole in its wing? Answer to both is yes if the physics of both result in enough force being applied to what is being hit. It is a little equation called Force equals mass x acceleration (F=ma). Quote Link to post Share on other sites
GreyGhost Posted August 31, 2011 Share Posted August 31, 2011 NACES equipped F-14D Tomcats had cutters attached to the seats ... Gregg Quote Link to post Share on other sites
Jinro Posted August 31, 2011 Share Posted August 31, 2011 I agree injuries to the brain inside the skull can be deadly. But I wonder what kind of g's would be entailed as such in the movie. If Mythbusters speaks the truth, it takes ~100Gs to the head to cause death. Maverick being unable to reach ejection handle due to centripetal force totally feasible. That's why there are also ejection handles in between the pilot's legs or on the side of the seat :unsure: Quote Link to post Share on other sites
Wayne S Posted September 1, 2011 Share Posted September 1, 2011 I agree injuries to the brain inside the skull can be deadly. But I wonder what kind of g's would be entailed as such in the movie. No clue what Gs would be in the movie on the persons body "Z axis pushing down? maybe 20G?", Tho when speaking of a head injury/ brain for cause of death with Gs, One is really speaking of impact force. Instance people that die from motorcycle accidents from their head hitting the pavement/hard surface is really not high in speed at all, most of the time, it is their head "around 10Lbs" In a free fall from a distance/height of maybe 6ft tops. Quote Link to post Share on other sites
Les / Creative Edge Photo Posted September 1, 2011 Author Share Posted September 1, 2011 No clue what Gs would be in the movie on the persons body "Z axis pushing down? maybe 20G?", Tho when speaking of a head injury/ brain for cause of death with Gs, One is really speaking of impact force. Instance people that die from motorcycle accidents from their head hitting the pavement/hard surface is really not high in speed at all, most of the time, it is their head "around 10Lbs" In a free fall from a distance/height of maybe 6ft tops. aka: Indian Larry's passing a few years back while trick riding on his custom chopper even at parking lot speeds and without a helmet on. Quote Link to post Share on other sites
RRTRENT Posted September 1, 2011 Share Posted September 1, 2011 When I was in the USAF the statistic at that time was about 69% survived ejection,but there were a bunch of injuries.Another stat I saw one time was that the Navy lost 48 planes in TF-30 stall related accidents. Quote Link to post Share on other sites
spike7451 Posted September 1, 2011 Share Posted September 1, 2011 On the older seats your spine could be compressed by up to 4 inches & the was a limit to the amount of ejections one could do before being grounded,IIRC it was 4 in the RAF,that was mainly due to the way the seats operated back then,nowadays they are literally computer controlled & with sensors that can detect attitude ect & correct the sequence of ejection to maximize survivability. Quote Link to post Share on other sites
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