There's a very fine line between keeping your chin up, and sticking your neck out.
6 June 1971
Near Duarte, California
Midair Collision:
McDonnell-Douglas DC-9-31, N9345/ USMC F-4B Phantom II, 151458, VMFA-323
50 Fatal, 1 Uninjured
In the previous accident thread we discussed, I wrote about a civilian/military midair collision that occurred in IMC. Today's discussion will center on a civilian/military midair collision that occurred in near perfect VMC weather, about as CAVU as is possible. It's amazing that we, to this day, still suffer midair collisions in the frequency we do; in near perfect weather and outside the normal "crunch points", such as an airport traffic pattern or other highly congested areas where the threat of a midair would reasonably be more expected. A lot of stock has been put into the concept of "see and avoid"; that concept being hammered home as both a basic tenant of airmanship, as well as being regulatory. While collision-avoidance helpers such as ATC radar, TCAS I/II, and even air-to-air radar, are all good things to have; nothing replaces the old fashioned, tried-and-true Mark 1 human eyeball. 14 CFR 91.113(b) covers the concept that when conditions allow, such as VMC, keeping an eye out for what's around you is indispensible as well as required. Both in airspace where VFR traffic mixes, and even more especially in airspace where VFR vs IFR is likely, since the natural pilot tendency is to relax somewhat when under the "protection" of ATC radar. That is, it's the pilot-in-command's responsibility to see and avoid other traffic. Unfortunately, there's limited time for relaxing while flying, since potential midair collisions normally provide very little time for the pilots involved to detect/assess/avoid the rapidly progressing impact, especially at angles where high closure rates are occurring and cockpit or aircraft "blind spots" are in play. Over-reliance on any technology crutch for collision avoidance is very risky; as is reliance on the "big sky, little airplane" theory. The Grim Reaper of aviation awaits anyone who doesn't respect his authority, as the crew of both aircraft involved in this collision found out that fateful June day in 1971.
The weather in the Los Angeles, California area on the early evening of 6 June 1971 was characterized by mid-level thin-scattered to broken clouds, as well as low-level haze common to the LA basin. On this evening, the crew of Hughes Air West flight 706, a DC-9-31, was preparing for a regularly scheduled trip (RW706) starting from Los Angeles International (KLAX) and terminating in Seattle, Washington (KSEA) with intermediate stops in the cities of Salt Lake City, Utah; Boise and Lewiston, Idaho; and Pasco and Yakima, Washington. Onboard were the crew of two pilots and 3 flight attendants, as well as 44 passengers. At 1802 PST, Flight 706 departed the Los Angeles airport and proceeded via radar vectors and climb on course to Salt Lake City.
US Marine Corps F-4B Phantom II 151458, assigned to Fixed-Wing Marine Fighter/Attack Squadron 323 (VMFA-323), had departed two days prior on Friday, 4 June, as #2 of a 2-ship section weekend cross-country training flight from Marine Corps Air Station (MCAS) El Toro, California to RON at McChord Air Force Base (AFB), Washington, located in Tacoma. The flight to McChord AFB had been relatively uneventful, with an enroute fuel stop made at McClellan AFB, California, in Sacramento. The only problem encountered during this day of flying was the failure of the Identification Friend or Foe (IFF) sets in both aircraft. IFF is the same as a civilian Mode C transponder, with some addtional ID features installed specific to military operations. In spite of this failure in both aircraft, the mission was allowed to proceed under IFR by ATC, and continued with the section being kept clear of Positive Control Airspace (now known as Class A airspace post-1990). On 5 June, the section of F-4s departed McChord AFB for the flight back to El Toro, with an enroute fuel stop at Mountain Home AFB, Idaho. As during the previous day, this flight wasn't without problems, as now the UHF comm radio in the #2 jet (458) failed during final approach to Mountain Home. On the ground, further problems were discovered with other systems on 458 including the previously noted inoperative IFF, the inoperative UHF communications radio, and now a leaking Liquid Oxygen (LOX) system and severly degraded air-to-air search radar. Upon discussion of the situation, it was decided that the #1 F-4 would depart single-ship and return to El Toro, while the crew of 458 would remain at Mountain Home and await repairs to their aircraft. Line maintenance at Mountain Home fixed the UHF radio, but didn't have the necessary parts to fix the transponder, oxygen system, or radar. Consequently, the crew was directed by squadron leadership to depart for Naval Auxilary Air Station Fallon, Nevada the next day, 6 June, in order to bring the jet to the nearest naval facility for repairs and to make a fuel stop.
On Sunday, 6 June, the crew of 458 departed Mountain Home for Fallon. During this flight, the oxygen system failed totally and was switched off. The rest of the flight to Fallon was uneventful. Following arrival at Fallon, it was determined by maintenance there that suitable repairs would not be able to be made to 458. The crew of 458 queried their home station, and were advised to return to El Toro low-level in order to mitigate the need for oxygen from the now-broken system. Following refueling, the crew of 458 filed a VFR flight plan with the routing of Fallon, direct Fresno, Bakersfield, Los Angeles to El Toro; remaining underneath the PCA at all times. After departing Fallon NAAS at 1716 PST, the flight initially climbed to 1500' and further climbed to 15,500' in order to cross a mountain range, descending to 5,500' following the crossing, remaining at that altitude until reaching Bakersfield. The crew of 458 contacted Bakersfield FSS to make a position report and check El Toro field weather. The crew deviated east of course and descended to 1000 AGL and 300-350 knots in order to continue their low flight profile, as well as keep clear of the LA basin air traffic to their west, especially with an inop IFF system. About 15 miles northwest of Palmdale, California, the crew of 458 began encountering the low-level haze that was blanketing most of that part of southern California. In order to stay VMC, the crew of 458 decided to return to 15,500' and commenced a military-power climb at 5000+ fpm. Leading the level-off altitude, the pilot of 458 performed an aileron roll in order to maintain positive G force on the aircraft and expedite the level off. During this roll, the backseat Radar Intercept Officer (RIO) had been following the aircraft's progress via ground mapping, and was heads-down in the radar scope updating the radar picture; the air-to-ground portion of the radar was working acceptably, whereas the air-to-air portion of the radar was broken. As he was looking down into his scope, and approximately 1 minute and 20 seconds after level off at 15,500', the RIO picked up a a dot in his peripheral vision of the DC-9, at his 1 to 2 o'clock coming head-on, and slightly lower, and unmoving but rapidly growing in size. Flight 706 was still in their enroute climb at this time and flying at 400 KTAS, while 458 was level at 15,500' and 420 KTAS. The RIO shouted a "break" warning to the pilot while the pilot simultaneously rolled the F-4 rapidly into a descending left turn, indicating that the pilot too had noticed the DC-9 at the same time as the RIO. The F-4's right wing impacted the left front quarter of the DC-9 from a position just behind the cockpit, going from the DC-9s 10 o'clock to it's 4 o'clock position. The F-4s right wing cleanly sliced the DC-9 in half longitudinally, separating the cockpit from the rest of the fuselage. The DC-9's cockpit section tumbled to earth, while the aft fuselage from about Row 3 aft, minus the cockpit, continued in level flight for about 10 seconds before starting a wide-spiraling dive to the ground. The F-4 began tumbling violently along the lateral axis (end over end) following the collision. The RIO, sensing the F-4 to be unrecoverable, initiated ejection via his alternate ejection handle. Canopy separation, ejection sequencing, seat-man separation, and parachute inflation were all uneventful, and the RIO parachuted into a canyon uninjured. The F-4s pilot didn't eject. It was later found that the pilot had initiated ejection via his alternate ejection handle, but the canopy failed to separate from the F-4. In the F-4s system, if the canopy doesn't separate, the ejection seat is inhibited from firing. The F-4 pilot remained with the aircraft and was killed. All 49 passengers and crew aboard the DC-9 were fatally injured. The wreckage of both aircraft came down in the eastern slopes of Mt. Bliss near Duarte, California.
Probable Cause
*Visual Lookout- Inadequate- Flight Crew RW706
*Visual Lookout- Inadequate- Flight Crew 151458
Secondary Factors
*Closure Rate- High- Both Aircraft
*Coverage Limited- ATC Radar
*Separation Effectiveness Limited- ATC Radar
Tertiary Factors
*Radar Assistance To VFR Aircraft- Not Used- Crew of 151458
MikeD says
This accident, like so many before it and so many after it, highlights how midair collisions can happen on the clearest of weather days. The crews of both aircraft were following appropriate regulations, and yet, still managed to hit each other. Let's examine their individual situations more closely:
DC-9, RW706
By all accounts, it is assumed that the crew of RW706 was carrying out their normal duties for the phase of flight they were in at the time, at least according to ATC communications. Cockpit Voice Recorder information was unavailable due to excessive impact and fire damage sustained by the CVR unit. RW706 was climbing past 15,500 and was handing off to Los Angeles ARTCC, following termination with Los Angeles TRACON. From the Flight Data Recorder accounts, which were undamaged, RW706s flightpath and airspeed/altitude parameters match what ATC radar displayed. The FDR showed that RW706 was in a constant climb schedule all the way to impact, indicating that the crew of RW706 didn't see the F-4 and consequently, took no evasive action; an indication confirmed by the eyewitness account of the F-4s RIO. In cockpit visibility studies completed during the investigation process, it was recognized by the NTSB that the crews of both aircraft had the other aircraft in a blind-spot of cockpit structure during much of the time the aircraft were closing on each other, thus severely limiting the ability of both crews to see each other if they never moved their heads from their seating positions. For the DC-9, it was assessed that the F-4 was behind the front windscreen quarterpanel on the Captain's side from the last 40 seconds to impact. At 40 seconds out and beyond, at the closure rates both aircraft had on each other as well as the near- head on aspect angle to each other, the F-4 wouldn't have been visible to the crew of RW706, due to it's far distance from the DC-9 making it little bigger than a small speck by the time it went behind the windscreen, and likely not reappearing until it rapidly "blossomed" in size 2 to 3 seconds prior to impact. The co-pilot, on the far side of the cockpit, likely had no chance to see across the cockpit and detect the F-4. Similiarly, the visibility study showed that the DC-9 was behind the right quarterpanel of the F-4s front canopy from the entire time it would have been visible to the F-4s pilot, up to when it rapidly blossomed in the final seconds. In spite of the poor all-around visibility of the F-4s rear cockpit, especially in the forward hemisphere where visibility is blocked by the front cockpit ejection seat, the DC-9 would've been in the RIOs eyesight from 80 seconds prior to impact, nearly all the way to impact; though due to the closure speeds, the DC-9 likely wouldn't have been visible to the naked eye until about the 10 second to impact point.
F-4B, 151458
The crew of 458 was plagued by aircraft problems from the start of their mission on 4 June. Beginning with the inoperable IFF, the oxygen problems, and the degraded air-to-air radar; all of these problems remained unfixed due to the unavailability of other than transient-maintenance (light maintenance) on a weekend. As a result, the crew was forced to fly with these inoperable and degraded systems. Though approved through the squadron command, and perfectly legal regulations-wise, each problem in and of itself created a restriction to the flight. The inop IFF precluded operations in Positive Control Airspace (Class A airspace); the inop oxygen system precluded long-duration flight above 15,000, and forced the crew to fly lower level at high speed. A little out of the ordinary, but nothing more than a standard VFR flight to accomplish. 250 knots below 10,000 doesn't apply to a number of military fighter-type aircraft due to specific operational aircraft limitations, hence the higher speed. In order to get some training value from the mission back to base, the crew decided to run a radar mapping exercise while proceeding back to El Toro, since the air-to-ground portion of the radar was still operable. This was done at low-level, and since low-level was the way the crew of 458 was going to return home, why not incorporate some training into the profile? By all accounts, the crew of 458 made prudent decisions in remaining low level and deviating flightpath to avoid known higher traffic density areas. The only unforseen problem they ran into was the low-level haze in the Palmdale area which forced them to climb back to a proper VFR hemispheric altitude, in this case 15,500, again a legal altitude, but one that unknowingly placed them in a somewhat higher traffic density zone for the area they were in. Leveling off, the pilot executed an aileron roll, common in fighter aircraft following high rates of climb in order to avoid needing negative G pushovers in order to level off. Also, a roll gives the chance to make a "belly check" of what's underneath you, while simulataneously the movement of such a maneuver making you visible to another aircraft, rather than being an unmoving dot in someone else's windscreen. All legal maneuvers, but the roll being about 1 minute 20 seconds prior to the collision, the maneuver and any part of the F-4 would've been invisible to the DC-9 crew at the ranges from each other they were at. As a tertiary factor, it was suggested that the crew of 458 should've called for VFR flight following. Though a prudent move, it's effectiveness is questionable. For one, 458 didn't have an operable transponder, making it very difficult, if not impossible for ATC to ever get a paint on the F-4. Due to that fact, as well as the fact that VFR flight following is lowest priority for ATC, it's likely that with ATC not ever knowing where exactly 458 was at any given time, no traffic warnings would be given, since no conflicts would ever be noted. In spite of all these limitations working against both the DC-9 and F-4 crew, the F-4 RIO was still able to get a tally on the DC-9 at end game; albeit too late for the collision to be avoided. There was some light speculation that had the F-4 broke right, into the DC-9, as opposed to left, away from the DC-9, the collision might have been avoided or less damaging. But this is all pure speculation with no factual evidence basis. The general consensus is that in the time it took for the F-4 crew to see the DC-9, process what they were seeing, physically make the decision and physically react, it still would've been too late.
An Interesting Sidenote
It's a common expression in aviation that the "rules are written in blood," that is, many new rules and regulations in aviation are the direct result of findings from an aviation accident. This accident resulted in two very common things we see in aviation today:
1. The Cockpit Area Microphone: Cockpit Voice Recorders today are equipped with specific microphones attached to the crew positions in an airliner cockpit, so it can be readily identified who is talking on the CVR, even in a degraded, or poor quality, recording. Previous to this, the CVR was no better than a tape recorder in the cockpit with "distant" sounding voices on tape, depending on which way the crewmember was facing or their distance from the recorder. Following this accident, CVRs began getting specific microphones. These CAMs are identified in CVR transcript printouts as CAM-1, CAM-2, CAM-3, etc for showing dialouge spoken from the Captain, First Officer, and Second Officer/Flight Engineer in a given airliner cockpit; thus making CVR deciphering post-accident, much easier.
2. The VFR Terminal Area Chart: In an effort to create map products that depict a heavy terminal area in better detail than the Sectional chart, the VFR Terminal Area Chart was developed in order to depict airspace in the, then-known, Terminal Control Areas (TCA...now known as Class B airspace post-1990) giving a visual depiction of airports, and VFR and IFR routes inside the area for VFR pilots to use when operating in and around these areas VFR. Named after the TCA, the Terminal Area Charts have retained their name, even though the airspace was renamed, and the charts resemble a more-detailed Sectional chart; which in a sense, they are...the Sectional being 1:500,000 scale, while the TAC chart is 1:250,000 scale. The first VFR Terminal Area Chart was created for testing for the Chicago TCA in 1970/71. The Terminal Area Chart is an integral part of VFR Class B airspace operations to this day.
Regulation-wise, the role of such helpers as ATC, maps, TCAS, etc is well-defined; for example, ATCs prime job being to sequence and separate IFR vs IFR traffic. Similiarly, the role of the pilot is also well defined, again in 14 CFR 91.113(b): In VMC, it's ultimately the pilot's responsibility to assure collision avoidance, regardless of whether you're proceeding IFR or VFR. Nothing can replace the human eyeball coupled with the human brain in being the highest piece of technology in the cockpit for collision avoidance. In this sense, like the title of this thread states, Look Out To Live takes on a meaning all it's own.
MikeD
The above is not intended to be an undue criticism of the person or persons involved in the incident described. Instead, the analysis presented is intended to further the cause of flight safety and help to reduce accidents and incidents by educating pilots through the sacrifices of others in our profession.
Pictures:
Hughes Air West DC-9-31, N9345 / RW706
USMC F-4N Phantom II (modified F-4B) 152243 / WS-04, VMFA-323. Sister aircraft to F-4B Phantom II 151458 from same unit.
Official photo of RW-706 impact location in canyon on eastern slopes of Mt. Bliss, Duarte, Calif.
6 June 1971
Near Duarte, California
Midair Collision:
McDonnell-Douglas DC-9-31, N9345/ USMC F-4B Phantom II, 151458, VMFA-323
50 Fatal, 1 Uninjured
In the previous accident thread we discussed, I wrote about a civilian/military midair collision that occurred in IMC. Today's discussion will center on a civilian/military midair collision that occurred in near perfect VMC weather, about as CAVU as is possible. It's amazing that we, to this day, still suffer midair collisions in the frequency we do; in near perfect weather and outside the normal "crunch points", such as an airport traffic pattern or other highly congested areas where the threat of a midair would reasonably be more expected. A lot of stock has been put into the concept of "see and avoid"; that concept being hammered home as both a basic tenant of airmanship, as well as being regulatory. While collision-avoidance helpers such as ATC radar, TCAS I/II, and even air-to-air radar, are all good things to have; nothing replaces the old fashioned, tried-and-true Mark 1 human eyeball. 14 CFR 91.113(b) covers the concept that when conditions allow, such as VMC, keeping an eye out for what's around you is indispensible as well as required. Both in airspace where VFR traffic mixes, and even more especially in airspace where VFR vs IFR is likely, since the natural pilot tendency is to relax somewhat when under the "protection" of ATC radar. That is, it's the pilot-in-command's responsibility to see and avoid other traffic. Unfortunately, there's limited time for relaxing while flying, since potential midair collisions normally provide very little time for the pilots involved to detect/assess/avoid the rapidly progressing impact, especially at angles where high closure rates are occurring and cockpit or aircraft "blind spots" are in play. Over-reliance on any technology crutch for collision avoidance is very risky; as is reliance on the "big sky, little airplane" theory. The Grim Reaper of aviation awaits anyone who doesn't respect his authority, as the crew of both aircraft involved in this collision found out that fateful June day in 1971.
The weather in the Los Angeles, California area on the early evening of 6 June 1971 was characterized by mid-level thin-scattered to broken clouds, as well as low-level haze common to the LA basin. On this evening, the crew of Hughes Air West flight 706, a DC-9-31, was preparing for a regularly scheduled trip (RW706) starting from Los Angeles International (KLAX) and terminating in Seattle, Washington (KSEA) with intermediate stops in the cities of Salt Lake City, Utah; Boise and Lewiston, Idaho; and Pasco and Yakima, Washington. Onboard were the crew of two pilots and 3 flight attendants, as well as 44 passengers. At 1802 PST, Flight 706 departed the Los Angeles airport and proceeded via radar vectors and climb on course to Salt Lake City.
US Marine Corps F-4B Phantom II 151458, assigned to Fixed-Wing Marine Fighter/Attack Squadron 323 (VMFA-323), had departed two days prior on Friday, 4 June, as #2 of a 2-ship section weekend cross-country training flight from Marine Corps Air Station (MCAS) El Toro, California to RON at McChord Air Force Base (AFB), Washington, located in Tacoma. The flight to McChord AFB had been relatively uneventful, with an enroute fuel stop made at McClellan AFB, California, in Sacramento. The only problem encountered during this day of flying was the failure of the Identification Friend or Foe (IFF) sets in both aircraft. IFF is the same as a civilian Mode C transponder, with some addtional ID features installed specific to military operations. In spite of this failure in both aircraft, the mission was allowed to proceed under IFR by ATC, and continued with the section being kept clear of Positive Control Airspace (now known as Class A airspace post-1990). On 5 June, the section of F-4s departed McChord AFB for the flight back to El Toro, with an enroute fuel stop at Mountain Home AFB, Idaho. As during the previous day, this flight wasn't without problems, as now the UHF comm radio in the #2 jet (458) failed during final approach to Mountain Home. On the ground, further problems were discovered with other systems on 458 including the previously noted inoperative IFF, the inoperative UHF communications radio, and now a leaking Liquid Oxygen (LOX) system and severly degraded air-to-air search radar. Upon discussion of the situation, it was decided that the #1 F-4 would depart single-ship and return to El Toro, while the crew of 458 would remain at Mountain Home and await repairs to their aircraft. Line maintenance at Mountain Home fixed the UHF radio, but didn't have the necessary parts to fix the transponder, oxygen system, or radar. Consequently, the crew was directed by squadron leadership to depart for Naval Auxilary Air Station Fallon, Nevada the next day, 6 June, in order to bring the jet to the nearest naval facility for repairs and to make a fuel stop.
On Sunday, 6 June, the crew of 458 departed Mountain Home for Fallon. During this flight, the oxygen system failed totally and was switched off. The rest of the flight to Fallon was uneventful. Following arrival at Fallon, it was determined by maintenance there that suitable repairs would not be able to be made to 458. The crew of 458 queried their home station, and were advised to return to El Toro low-level in order to mitigate the need for oxygen from the now-broken system. Following refueling, the crew of 458 filed a VFR flight plan with the routing of Fallon, direct Fresno, Bakersfield, Los Angeles to El Toro; remaining underneath the PCA at all times. After departing Fallon NAAS at 1716 PST, the flight initially climbed to 1500' and further climbed to 15,500' in order to cross a mountain range, descending to 5,500' following the crossing, remaining at that altitude until reaching Bakersfield. The crew of 458 contacted Bakersfield FSS to make a position report and check El Toro field weather. The crew deviated east of course and descended to 1000 AGL and 300-350 knots in order to continue their low flight profile, as well as keep clear of the LA basin air traffic to their west, especially with an inop IFF system. About 15 miles northwest of Palmdale, California, the crew of 458 began encountering the low-level haze that was blanketing most of that part of southern California. In order to stay VMC, the crew of 458 decided to return to 15,500' and commenced a military-power climb at 5000+ fpm. Leading the level-off altitude, the pilot of 458 performed an aileron roll in order to maintain positive G force on the aircraft and expedite the level off. During this roll, the backseat Radar Intercept Officer (RIO) had been following the aircraft's progress via ground mapping, and was heads-down in the radar scope updating the radar picture; the air-to-ground portion of the radar was working acceptably, whereas the air-to-air portion of the radar was broken. As he was looking down into his scope, and approximately 1 minute and 20 seconds after level off at 15,500', the RIO picked up a a dot in his peripheral vision of the DC-9, at his 1 to 2 o'clock coming head-on, and slightly lower, and unmoving but rapidly growing in size. Flight 706 was still in their enroute climb at this time and flying at 400 KTAS, while 458 was level at 15,500' and 420 KTAS. The RIO shouted a "break" warning to the pilot while the pilot simultaneously rolled the F-4 rapidly into a descending left turn, indicating that the pilot too had noticed the DC-9 at the same time as the RIO. The F-4's right wing impacted the left front quarter of the DC-9 from a position just behind the cockpit, going from the DC-9s 10 o'clock to it's 4 o'clock position. The F-4s right wing cleanly sliced the DC-9 in half longitudinally, separating the cockpit from the rest of the fuselage. The DC-9's cockpit section tumbled to earth, while the aft fuselage from about Row 3 aft, minus the cockpit, continued in level flight for about 10 seconds before starting a wide-spiraling dive to the ground. The F-4 began tumbling violently along the lateral axis (end over end) following the collision. The RIO, sensing the F-4 to be unrecoverable, initiated ejection via his alternate ejection handle. Canopy separation, ejection sequencing, seat-man separation, and parachute inflation were all uneventful, and the RIO parachuted into a canyon uninjured. The F-4s pilot didn't eject. It was later found that the pilot had initiated ejection via his alternate ejection handle, but the canopy failed to separate from the F-4. In the F-4s system, if the canopy doesn't separate, the ejection seat is inhibited from firing. The F-4 pilot remained with the aircraft and was killed. All 49 passengers and crew aboard the DC-9 were fatally injured. The wreckage of both aircraft came down in the eastern slopes of Mt. Bliss near Duarte, California.
Probable Cause
*Visual Lookout- Inadequate- Flight Crew RW706
*Visual Lookout- Inadequate- Flight Crew 151458
Secondary Factors
*Closure Rate- High- Both Aircraft
*Coverage Limited- ATC Radar
*Separation Effectiveness Limited- ATC Radar
Tertiary Factors
*Radar Assistance To VFR Aircraft- Not Used- Crew of 151458
MikeD says
This accident, like so many before it and so many after it, highlights how midair collisions can happen on the clearest of weather days. The crews of both aircraft were following appropriate regulations, and yet, still managed to hit each other. Let's examine their individual situations more closely:
DC-9, RW706
By all accounts, it is assumed that the crew of RW706 was carrying out their normal duties for the phase of flight they were in at the time, at least according to ATC communications. Cockpit Voice Recorder information was unavailable due to excessive impact and fire damage sustained by the CVR unit. RW706 was climbing past 15,500 and was handing off to Los Angeles ARTCC, following termination with Los Angeles TRACON. From the Flight Data Recorder accounts, which were undamaged, RW706s flightpath and airspeed/altitude parameters match what ATC radar displayed. The FDR showed that RW706 was in a constant climb schedule all the way to impact, indicating that the crew of RW706 didn't see the F-4 and consequently, took no evasive action; an indication confirmed by the eyewitness account of the F-4s RIO. In cockpit visibility studies completed during the investigation process, it was recognized by the NTSB that the crews of both aircraft had the other aircraft in a blind-spot of cockpit structure during much of the time the aircraft were closing on each other, thus severely limiting the ability of both crews to see each other if they never moved their heads from their seating positions. For the DC-9, it was assessed that the F-4 was behind the front windscreen quarterpanel on the Captain's side from the last 40 seconds to impact. At 40 seconds out and beyond, at the closure rates both aircraft had on each other as well as the near- head on aspect angle to each other, the F-4 wouldn't have been visible to the crew of RW706, due to it's far distance from the DC-9 making it little bigger than a small speck by the time it went behind the windscreen, and likely not reappearing until it rapidly "blossomed" in size 2 to 3 seconds prior to impact. The co-pilot, on the far side of the cockpit, likely had no chance to see across the cockpit and detect the F-4. Similiarly, the visibility study showed that the DC-9 was behind the right quarterpanel of the F-4s front canopy from the entire time it would have been visible to the F-4s pilot, up to when it rapidly blossomed in the final seconds. In spite of the poor all-around visibility of the F-4s rear cockpit, especially in the forward hemisphere where visibility is blocked by the front cockpit ejection seat, the DC-9 would've been in the RIOs eyesight from 80 seconds prior to impact, nearly all the way to impact; though due to the closure speeds, the DC-9 likely wouldn't have been visible to the naked eye until about the 10 second to impact point.
F-4B, 151458
The crew of 458 was plagued by aircraft problems from the start of their mission on 4 June. Beginning with the inoperable IFF, the oxygen problems, and the degraded air-to-air radar; all of these problems remained unfixed due to the unavailability of other than transient-maintenance (light maintenance) on a weekend. As a result, the crew was forced to fly with these inoperable and degraded systems. Though approved through the squadron command, and perfectly legal regulations-wise, each problem in and of itself created a restriction to the flight. The inop IFF precluded operations in Positive Control Airspace (Class A airspace); the inop oxygen system precluded long-duration flight above 15,000, and forced the crew to fly lower level at high speed. A little out of the ordinary, but nothing more than a standard VFR flight to accomplish. 250 knots below 10,000 doesn't apply to a number of military fighter-type aircraft due to specific operational aircraft limitations, hence the higher speed. In order to get some training value from the mission back to base, the crew decided to run a radar mapping exercise while proceeding back to El Toro, since the air-to-ground portion of the radar was still operable. This was done at low-level, and since low-level was the way the crew of 458 was going to return home, why not incorporate some training into the profile? By all accounts, the crew of 458 made prudent decisions in remaining low level and deviating flightpath to avoid known higher traffic density areas. The only unforseen problem they ran into was the low-level haze in the Palmdale area which forced them to climb back to a proper VFR hemispheric altitude, in this case 15,500, again a legal altitude, but one that unknowingly placed them in a somewhat higher traffic density zone for the area they were in. Leveling off, the pilot executed an aileron roll, common in fighter aircraft following high rates of climb in order to avoid needing negative G pushovers in order to level off. Also, a roll gives the chance to make a "belly check" of what's underneath you, while simulataneously the movement of such a maneuver making you visible to another aircraft, rather than being an unmoving dot in someone else's windscreen. All legal maneuvers, but the roll being about 1 minute 20 seconds prior to the collision, the maneuver and any part of the F-4 would've been invisible to the DC-9 crew at the ranges from each other they were at. As a tertiary factor, it was suggested that the crew of 458 should've called for VFR flight following. Though a prudent move, it's effectiveness is questionable. For one, 458 didn't have an operable transponder, making it very difficult, if not impossible for ATC to ever get a paint on the F-4. Due to that fact, as well as the fact that VFR flight following is lowest priority for ATC, it's likely that with ATC not ever knowing where exactly 458 was at any given time, no traffic warnings would be given, since no conflicts would ever be noted. In spite of all these limitations working against both the DC-9 and F-4 crew, the F-4 RIO was still able to get a tally on the DC-9 at end game; albeit too late for the collision to be avoided. There was some light speculation that had the F-4 broke right, into the DC-9, as opposed to left, away from the DC-9, the collision might have been avoided or less damaging. But this is all pure speculation with no factual evidence basis. The general consensus is that in the time it took for the F-4 crew to see the DC-9, process what they were seeing, physically make the decision and physically react, it still would've been too late.
An Interesting Sidenote
It's a common expression in aviation that the "rules are written in blood," that is, many new rules and regulations in aviation are the direct result of findings from an aviation accident. This accident resulted in two very common things we see in aviation today:
1. The Cockpit Area Microphone: Cockpit Voice Recorders today are equipped with specific microphones attached to the crew positions in an airliner cockpit, so it can be readily identified who is talking on the CVR, even in a degraded, or poor quality, recording. Previous to this, the CVR was no better than a tape recorder in the cockpit with "distant" sounding voices on tape, depending on which way the crewmember was facing or their distance from the recorder. Following this accident, CVRs began getting specific microphones. These CAMs are identified in CVR transcript printouts as CAM-1, CAM-2, CAM-3, etc for showing dialouge spoken from the Captain, First Officer, and Second Officer/Flight Engineer in a given airliner cockpit; thus making CVR deciphering post-accident, much easier.
2. The VFR Terminal Area Chart: In an effort to create map products that depict a heavy terminal area in better detail than the Sectional chart, the VFR Terminal Area Chart was developed in order to depict airspace in the, then-known, Terminal Control Areas (TCA...now known as Class B airspace post-1990) giving a visual depiction of airports, and VFR and IFR routes inside the area for VFR pilots to use when operating in and around these areas VFR. Named after the TCA, the Terminal Area Charts have retained their name, even though the airspace was renamed, and the charts resemble a more-detailed Sectional chart; which in a sense, they are...the Sectional being 1:500,000 scale, while the TAC chart is 1:250,000 scale. The first VFR Terminal Area Chart was created for testing for the Chicago TCA in 1970/71. The Terminal Area Chart is an integral part of VFR Class B airspace operations to this day.
Regulation-wise, the role of such helpers as ATC, maps, TCAS, etc is well-defined; for example, ATCs prime job being to sequence and separate IFR vs IFR traffic. Similiarly, the role of the pilot is also well defined, again in 14 CFR 91.113(b): In VMC, it's ultimately the pilot's responsibility to assure collision avoidance, regardless of whether you're proceeding IFR or VFR. Nothing can replace the human eyeball coupled with the human brain in being the highest piece of technology in the cockpit for collision avoidance. In this sense, like the title of this thread states, Look Out To Live takes on a meaning all it's own.
MikeD
The above is not intended to be an undue criticism of the person or persons involved in the incident described. Instead, the analysis presented is intended to further the cause of flight safety and help to reduce accidents and incidents by educating pilots through the sacrifices of others in our profession.
Pictures:
Hughes Air West DC-9-31, N9345 / RW706
USMC F-4N Phantom II (modified F-4B) 152243 / WS-04, VMFA-323. Sister aircraft to F-4B Phantom II 151458 from same unit.
Official photo of RW-706 impact location in canyon on eastern slopes of Mt. Bliss, Duarte, Calif.
