The F-35 That Froze. And Crashed.
I read about the incident, I think, almost the next day, but it didn't really interest me. Well, the F-35 crashed and crashed, everyone was alive. But after reading the article about penguins (here it is) I wanted to clarify something. The author of the article wrote that the circumstances of what happened were classified and only recently and accidentally surfaced, that they fought with the stupid computer, but could not overcome it, and then the pilot in despair ejected himself away from the crazy plane. But I read the article in twz and saw a short video by a certain TheIntelFrost, who in turn simply copy-pasted this video from the Anchorage Daily News. The video was obviously filmed on a phone - how else, because it is always at hand - but even so it is noticeable that the landing gear of the plane was released.
Both the twz article and the video happened on the same day as the incident at the airbase. And the airbase press service, by the way, issued a press release about the incident on the same day – that is, there was no secret here either.
Well, the fact that the investigation report, again not at all classified, was released only in July – that's still fast. And as for "they fought, but couldn't" – that was also not the case.
And this report is presented to your attention.
All such documents have the same style of presentation, when the description of the incident is repeated several times, each time in more detail. I do not like this system, and therefore I will retell it in my own way.
Abbreviations used in the document:
MA - the plane that crashed
MR - the pilot of the plane that crashed
MW – wingman pilot
LG – Landing Gear, chassis
NLG – Nose Landing Gear, nose landing gear
NLW – Nose Landing Wheel, landing gear nose wheel
NWS – Nose Wheel Steering System
WoW – Wheel Weight Sensors
It should be said that although the report is classified as unclassified, it lacks certain tables that are constantly mentioned there, and in which, apparently, some figures and results obtained during the investigation were entered. Since they are not there, we will not mention them.
The MA (F-35A type, tactical serial 19-5535) was operated by the 355th Fighter Squadron, 354th Fighter Wing. The 354th Wing is the host of Eielson AFB, and the 355th Squadron operates the F-35As. Here they are at the air base, and there are a lot of them:
Photo from militarywatchmagazine
Note: The F-35A is an aircraft with a conventional takeoff and landing method, "like an airplane", unlike the F-35B, which takes off with a short run and lands completely vertically.
The squadron's mission is to suppress enemy air defenses (where they found the enemy in Alaska is completely unclear. Bears? Eskimos? Canada?). The airbase is located 40 km southeast of Fairbanks and has existed since 1943, and during the war sometimes served as a stopover for aircraft being ferried to the USSR.
Since the incident happened in January, let's immediately look at the weather: the average January temperature in Fairbanks is -1.5 °C, and the very lowest temperature of -54 °C was recorded in January 1934.
On January 28, 2025, a flight of four F-35 fighters from the 355th Squadron was scheduled to fly as a simulated adversary (call sign YETI). The crashed aircraft had the call sign YETI-3, and its wingman was YETI-4.
Before departure, the flight received the necessary briefing and information on the weather conditions. The weather conditions were as follows: wind 10 m/sec direction 260, visibility 25 km, cloud cover 1300 m, ground temperature -18 °C, dew point -22 °C, and the predicted temperature at an altitude of 10 thousand feet = -29 °C. The MR pilot, as required, carried out a visual inspection of the aircraft together with the technician and found nothing. When starting the engine, the warning system issued a signal about a malfunction of the IPP - the integrated power unit. After the pilot performed all the necessary actions according to the checklist, the emergency signal disappeared.
Note: The IPP is the thing that supplies the airplane with electrical power when parked, starts the main engine, and then supplies electrical power and hydraulics during normal operation and an emergency. It's a compact gas turbine engine combined with a generator and hydraulic pump. The F-35 is heavily electrified, and anything that requires electrical power gets its power from this unit.
At 19:42 the aircraft left the hangar and headed to the takeoff point, where it remained for 40 minutes due to minor problems with other aircraft. Clearance for takeoff was received at 20:21, and during this time the aircraft remained in the open air, exposed to low temperatures. At 20:22 the MA aircraft took off and the pilot moved the landing gear control to the "UP" position.
At 20:23, when the aircraft's speed exceeded 275 knots, the "overspeed gear" symbol appeared on the malfunction panel. According to the Flight Manual, this signal appears when the aircraft has exceeded or may exceed the maximum flight speed at the current acceleration set for LG (apparently with the landing gear extended). The signal is issued with a lead time of 3 seconds. The warning system is triggered if the predicted or current indicated airspeed of the aircraft exceeds 300 knots (this is approximately 0,44 Mach), if the landing gear doors are not closed, the landing gear control handle is in the DOWN position, or the ALT GEAR EXTENSION command is issued.
Note: No explanation is given about the principle of operation of the landing gear retraction system, but it is possible that the landing gear control handle has three positions: UP, DOWN and OFF. Judging by other aircraft, in the UP position the landing gear retracts, after which the hydraulic system remains under pressure and holds the landing gear "pressed", and in the OFF position the pressure is released and the landing gear is mechanically locked.
As for ALT GEAR EXTENSION, this is an emergency release of the chassis.
This warning is common on F-35As during takeoff, and is especially true in cold conditions such as the one at Eielson AFB on the day of the accident. The MP pulled back on the control stick to raise the nose and simultaneously reduced the throttle to remain within the landing gear retraction speed. During this time, the landing gear retraction process appeared normal until a series of yellow and black symbols appeared on the NLG display indicating the landing gear status during retraction. The aircraft at this point slightly overspeeded to 308 knots for 7 seconds and then began to slow, and at 2023 the pilot radioed the flight, "warning 3 seconds, airspeed 275, nose not retracted." He then asked the flight leader for permission for him and his wingman to return to base, to the emergency area, to begin the landing gear checklist.
The pilot and wingman returned to the airbase emergency area at 9500 feet and contacted the controller, informing him that the nose gear was retracting extremely slowly and that the nose doors remained open. The pilot also informed the controller that the nose wheel was possibly damaged, that no overspeed had been detected, and that the wingman would now conduct an external inspection of his aircraft. The controller responded: "Understood, I'm looking at the landing gear emergency instructions and will contact you soon."
At 20:26 the wingman reported: "It looks like your hatch doors didn't close, there's about a 2-inch gap." The MA pilot and the controller found out that the next action, according to the instructions, was to re-release the landing gear. At 20:29 the landing gear was released and the pilot informed the controller: "No effect... three green marks", and then announced that he was beginning the checklist items to troubleshoot the nose wheel steering system.
The NWS DEGD malfunction signal first appeared at 20:24, but at 20:27 the pilot, after some manipulations according to the checklist, managed to remove the signal, and he even informed the dispatcher that he intended to release the wingman so that he could continue to perform the task together with the rest of the flight. However, the wingman soon reported: "Wait, your nose wheel is turned to the left by about 25 degrees.", after which the malfunction signal appeared again. The pilot then repeated to the controller what he was seeing in the cockpit: the landing gear handle was in the DOWN position, the landing gear indicator showed three green lights, indicating that all three landing gears were down and the airplane was in the "ready to land" configuration. The controller acknowledged the receipt and asked how much fuel was left - the pilot replied 14,5 (meaning thousands of pounds), or about 80%, and suggested that the situation was conducive to calling a "conference hotel".
Note: Conference hotel is a direct call to Lockheed engineers that can be initiated by the flight controller to discuss issues not covered in the Flight Manual.
While all this was being organized, the pilot attempted several S-maneuvers with G-forces up to 2,5, as well as a side slip to starboard to see if the nose wheel orientation would change. However, the wingman, after a visual inspection, reported that nothing had changed.
Finally, the controller informed the pilot that a call had been set up. Five Lockheed experts participated in the conference, including three landing gear systems engineers, a senior programmer, and a safety systems engineer. The 354th Wing's senior operations leader (OGL) also participated in the conference, but there are no recordings of his conversations because they were made on a personal phone. Among the information requested by the experts were fuel levels, nose gear direction, and health control codes. (by the word Health we mean the “health” of the aircraft, not the crew =))The experts did not request or receive information about the air temperature or where and when the malfunction occurred.
At 20:48, the controller asked the wingman to check the wheel direction again, to which he received the response "20 degrees". At 2051, the controller informed the MR pilot that experts were looking for a safe opportunity to abort the flight, and in this case that would mean a landing procedure "emergency braking with brake cable seizure."
Note: It turns out that not only deck planes have a landing hook, but also land planes. On land, it is used in emergency situations, and the airfield must have the appropriate equipment. Aircraft supplied to the allies generally do not have such hooks.
The controller advised the pilot to burn as much fuel as possible. In response, the pilot reminded the controller that according to the instructions, a landing with a cable grab should occur "on three points", that is, the nose wheel should be on the ground before the cable grabs it. The controller said that experts were working on this issue.
The requirements for the "tether grab" procedure state that veering off course after landing and/or excessive off-centering (especially on narrow runways) is not allowed, as this increases the likelihood of the aircraft overturning. That is, an off-center nose wheel can make it impossible to secure the tether safely.
The dispatcher reported the course of action suggested by the experts: perform a touch-and-go maneuver to check whether (the signal) from the WoW sensors could straighten the front wheel. (It's not entirely clear here, but the sensors themselves, of course, cannot straighten the position of the wheel. They must transmit a signal to the computer, and the computer must issue some commands to the actuators). The pilot responded by suggesting another option: touch-and-go with high vertical speed and an immediate upward turn, followed by a visual check of the wheel position by the follower.
At 21:13, the controller reported that the experts believed that the probability of a positive result from such a proposal was very small, but they agreed to try it – but only the main landing gear should touch the runway, without touching the nose wheel. After that, immediately gain altitude, regardless of the result, and let the wingman watch. The experts, the controller added, assumed a mechanical failure of some kind, because under normal circumstances it is impossible to turn the wheel with the landing gear extended. They believed that the centering cam had jammed, but they could not imagine how this had happened. The experts did not recommend landing with the brake cable caught, since an uncentered wheel could cause the aircraft to tip over.
At 21:19, the pilot performed the first touch-and-go, after which the wingman reported that the wheel was still turned 20 degrees to the left. The only change in the situation was that the "control system malfunction" indication could no longer be cleared by pressing the reset button. The pilot also transmitted five health control codes that had appeared to the controller, including those related to the left and right main landing gear weight sensors. The controller passed this information on to the experts.
The controller later recalled that the Lockheed engineers wanted to know about the nose wheel and showed no interest in the main gear codes. He could not recall whether the codes were transmitted "verbatim" or simply "reported." The OGL duty officer remembered that all the codes were transmitted to the engineers, who began to sort through the various options and compare them with the picture of what was happening. All three landing gear experts remembered that three health control codes were received from the controller, all related to the nose wheel.
According to the black box data, the main landing gear touched down at 21:18:45, and a second later a "control system malfunction" signal appeared, caused by malfunction signals from both right main landing gear weight sensors.
At this point, the MA pilot had no information about the cause of the signal. The pilot's helmet display and the panoramic display in the cockpit, on the forecast and "health" page of the aircraft, did not show any codes related to the control system. The checklist did not list all possible causes for the signal. After the pilot pressed the reset button, the signal disappeared, but a minute later it appeared again, confirming a malfunction of the weight sensors.
After the first touchdown, neither the MA pilot nor his wingman knew that the right main landing gear had not fully extended and was not symmetrical to the left landing gear. The only confirmation of the malfunction were the health control system codes.
The aircraft also issued a nose gear malfunction signal and a control system malfunction warning. In addition, the wingman's infrared sight video showed the nose wheel turned 20 degrees to the left and the right gear not fully extended.
After a conference discussion involving experts, the flight dispatcher and the duty officer, it was decided to conduct a second touchdown at "your normal" speed. This time, the MR pilot was to touch the runway with the nose gear, gain altitude, and the wingman was to conduct a visual inspection. The pilot confirmed the instructions received and proceeded to execute them.
At 21:48:15, the left main landing gear touched the ground first, followed by the nose wheel at 21:48:18. According to the video recording from the wingman and the black box data, after touchdown, the nose wheel turned slightly and remained at a position of 6 degrees to the left. In the next split second, namely 21:48:19, the MA pilot briefly turned on the afterburner to maximum and at 21:48:24 went up. At 21:48:32, the pilot again reset the control system malfunction signal with the reset button, and at 21:48:36, while climbing, the aircraft began to experience significant oscillations in course and pitch. The pilot tried to dampen the oscillations with the control stick, and at 21:48:41 he turned on the afterburner. At 21:48:42, the pilot attempted to create a bank to the left side, to which the aircraft responded with a sharp increase in pitch. At 21:48:43, the control stick returned to the neutral position, indicating that the pilot had released it. At 21:48:44, the pilot initiated ejection.
Upon further questioning, the pilot confirmed that the aircraft was experiencing sharp, uncontrollable yaw and pitch oscillations, which he attempted to counteract with the control stick. The left roll was his attempt to steer the aircraft away from a populated area. According to the black box, the ejection occurred at 21:48:44 local time, and the aircraft was in the following attitude: 370 feet above ground, 222 knots, nose up 40 degrees, left bank 38 degrees, 3g. After the ejection, the uncontrollable aircraft climbed to 3700 feet, then stalled and began a erratic fall.
Note: The video of the plane crash can be easily found if desired.
The crash and ejection were witnessed by many people at the airbase. The plane crashed slightly to the left of the runway where it had previously attempted to land, completely destroyed and burned. The pilot landed closer to the Sierra taxiway and managed to unhook his parachute before the crowd that had rushed to help him get to his feet. He then walked to the first aid room on his own.
The report also has a graph of the ejection in altitude/distance coordinates for some reason. It is unclear how this will help in the investigation, but you can see why not:
According to a report from Martin Baker (the manufacturer of the ejection seats), the ejection occurred at an altitude of 620 feet above ground level and an airspeed of 222 knots.
The report then immediately goes on to the results of the inspection of the aircraft's technical condition. It is very short, literally 10 lines. The Autonomic Logistics Information System program, which is used by technical specialists, was used for the inspection. It indicates what kind of maintenance and in what time frame the aircraft should receive according to JTD requirements, the results of checks and analyses, and in general everything related to the technical condition. According to the records, no deviations in the technical condition of the aircraft were noted, and all necessary procedures were carried out on time, and various minor faults noted in stories checks, did not relate to those that would lead to a ban on operation, nor to the incident that occurred.
Note: JTD, or Joint Technical Data, is a virtual library of all technical documentation created by Lockheed, constantly updated. It contains all the data on maintenance and spare parts, an interactive maintenance manual, troubleshooting steps according to their code, and through it you can also order anything missing.
Then, without any transition or intermediate conclusions, the section on checking the hydraulic fluid begins in the report. Apparently, all the inspectors already knew where and what to look for. Understanding what is happening is greatly hampered by the fact that the text constantly contains footnotes to missing tables. (Although, since we haven’t seen the tables, we don’t know whether they could have helped – the circle is closed).
The Landing Gear Fluid maintenance was performed on January 25, 2025, after 200 flight hours, as required by the JTD, by two technicians with qualification levels 5 and 7.
Note: Level 5 is an experienced technician who has completed basic training and has more than 18 months of experience, Level 7 is a senior specialist who can solve non-standard problems.
The procedure is not described in full, but it seems to be something like changing the brake fluid in a car: new fluid is pumped into the system until it squeezes out the old one. Here's what they write:
The procedure involves releasing the pneumatic system pressure and flushing the technical fluid in the landing gear struts. To accomplish this task, the technician loosens the pivot nut, releasing nitrogen and hydraulic fluid from the low-pressure port of the strut. (the BB-199 tab, apparently with the drawing, is missing. As for nitrogen, it is not stated anywhere what it is used for, but most likely in the shock absorbers of the struts). Hydraulic servicing is complete when a bubble-free flow of hydraulic fluid is visible through the clear tube mounted on the swivel nut. The pneumatic system must then be serviced by connecting a nitrogen cylinder located on a hand truck. This requires over 2 gallons of fluid to service all three legs.
When servicing the MA three days before the accident, the crew used no more than two gallons of hydraulic fluid because the team used only one hand truck and did not refill it during the procedure. Based on the amount of hydraulic fluid used, there was already water in the struts on January 23, 2025.
Note: It is unclear where the date of January 23 came from if maintenance was carried out on the 25th? It is also unclear on what basis such a conclusion was made. But we have what we have.
Following the incident, the Air Force Research Laboratory analyzed hydraulic fluid from the nose gear and right main gear. (Again, it is not said how they got it, since the plane burned. But, apparently, something survived. On the other hand, nothing is mentioned about the left strut). The laboratory found that approximately 1/3 of the liquid consisted of water.
In the 2,8 liters of liquid from the nose pillar, 1 liter of water was found, and in the 4 liters from the right pillar, 1,8 liters of water.
Hydraulic fluid for maintenance was taken from a drum in storage and loaded into the aircraft using a tank on a hand truck. The drum and tank were tested for contamination. Analysis of a sample from the drum showed contamination levels greater than 1024 ppm, more than twice the acceptable level for hydraulics. A sample from the tank on the hand truck also showed levels exceeding the acceptable level by a factor of two. Moreover, 1024 ppm was the maximum value for the device used for testing, so the actual contamination level could be much higher.
Hydraulic fluid is a HAZMAT hazardous material and must be handled according to specific requirements. HAZMAT enforcement at the airbase was poor due to insufficient staffing and frequent management changes, and no designated program manager had been appointed at the time of the accident.
In addition, HACOM program managers did not cap drums, did not check the maintenance of hand trucks, did not supervise the technicians who serviced the chassis, and did not record which drums the hydraulic fluid was taken from.
Note: HACOM – Hybrid Air vehicle Configuration Owner/Manager. This is apparently a unique position that only applies to the F-35. This is the engineer responsible for the technical status of a specific F-35 aircraft.
The hand pump attached to the barrel did not have a Teflon gasket that could have prevented contamination of the liquid if the barrel was not stored properly.
Additionally, there was no tracking of which drums were leaving the base or returning. As a result, the HAZMAT logs were incomplete. For example, a drum belonging to the 354th Wing that was sent to Kadena Air Base in Japan to support an exercise was overwritten after the squadron deployed to Kadena Air Base, making it impossible to track where it went during the exercise or where it ultimately ended up. It is possible that the hydraulic fluid used for maintenance on January 23 came from this drum, which had been in Japan for six weeks in a humid climate, but it is impossible to determine for sure. This was a direct violation of Air Force regulations that require hydraulic fluid to be stored in "a tightly closed container in a dry, well-ventilated place." Additionally, the hydraulic pump used to service the MA was marked as “empty/expended” as recently as April 2024, but was not scrapped. Despite this, it was used by the 355th Wing Maintenance Service and tested to contain approximately 33 percent water.
Incident of February 6, 2025
Nine days later, a similar incident occurred with another aircraft at the same airbase. After takeoff, the warning display showed a message about a malfunction of the nose landing gear. Following the checklist, the pilot released the landing gear and, after spinning in the air for 40 minutes, landed safely. An examination showed that the malfunction signal appeared due to the lack of locking of the upper roller of the retraction mechanism and the rotation of the nose wheel by 10 degrees to the left. Neither the pilot nor his wingman even noticed the rotation of this wheel. Recorder recordings showed that after touching the runway, the wheel turned slightly and remained in the position of 5 degrees to the left.
The aircraft was towed into a hangar with a constant temperature of 21°C and the nitrogen pressure in the landing gear shock absorbers was checked (yes, nitrogen shock absorbers!). It was then rolled outside again to -26°C and after 12 hours outside, it was jacked up until all the landing gear was off the ground. The landing gear was then measured. The aircraft's landing gear was unable to fully extend. If the main landing gear does not fully extend, the WoW weight sensors physically cannot function properly. All three landing gear were measured to be -10°C for the nose gear and -14°C for the right and left. The aircraft was lowered to the ground and towed back to a climate-controlled hangar at 21°C and left there for 12 hours, after which all three landing gear were drained of all fluid into glass jars. Significant amounts of water were found in the left main and front struts, while the sample from the right strut appeared to consist entirely of hydraulic fluid.
This incident and subsequent tests replicate the conditions experienced by the crashed aircraft. On both aircraft, water in the landing gear in sub-zero temperatures prevented the landing gear from fully extending.
Flight records show that the two aircraft had flown previously in the days preceding both incidents and had not experienced a similar malfunction. The ambient temperature during these sorties was not as cold as on the day of the incident. In addition, the time between leaving the heated shelter and takeoff was shorter than during the accident aircraft's January 28 and February 6 incident. It is likely that both aircraft were able to fly successfully despite the presence of water in the landing gear because the water did not have time to freeze before takeoff and landing gear retraction.
Chassis design
The landing gear system is a three-wheel design consisting of main landing gear, nose landing gear with a castor wheel, extension and retraction mechanisms, wheels and brakes, nose wheel steering, positioning and warning system, and a locking device.
Upper nose pillar retainer
The Gear Uplock Hook locks the nose gear in the raised (retracted) position. The lock is mechanically interlocked with the nose wheel bay door. When the gear is in the up position and locked, the door actuator closes the door, lifting the latch to the "LOCKED" position. When the latch is in the "LOCKED" position, the doors are closed and the aircraft is fully prepared to continue flight.
To ensure correct centering of the retracted wheel, centering cams are used.
Lower shock absorber of the nose strut
Next comes a description that I personally don't understand because it's not clear how the various parts interact when the chassis is retracted or extended.
One of the cams is mounted at the top of the landing gear strut and the other at the bottom of the strut. At the start of the accident flight, the nose gear did not fully extend due to ice forming in the strut. This caused a misalignment that prevented the strut's lifting hook from engaging the roller, causing damage to the metal adjacent to the roller.
For those who know, I give a fragment in English:
At the beginning of the mishap flight, the NLG didn't fully extend due to ice build-up within the NLG strut (Tab J-189). This ice buildup was the combination of significant water contamination in hydraulic fluid used to service the struts and ambient freezing temperatures around Eielson AFB (Tab J-189). The lack of full extension caused a misalignment that prevented the NLG uplock hook from catching the NLG uplock roller, causing damage to the metal adjacent to the roller (Tab J-185).
After the nose gear lift hook failed to engage the roller, the nose gear wheel deflected to the left by 17,5 degrees, creating an emergency situation and attempting a touch-and-go landing. After the initial touchdown, the right main and nose gear weight sensors indicated weight on the wheels, even though the aircraft was airborne. This was due to ice formation preventing the gear from fully extending or retracting. During the final takeoff, the nose gear wheel angle changed from 17,5 to 6 degrees after briefly touching down on the runway.
According to Lockheed Martin, if the main landing gear does not extend to its full length, the WoW weight sensors also fail to extend and report the weight ON the wheels. As will be shown below, the malfunction of the WoW sensors resulted in a change in the Control Law of Flight (CLAW).
Note: CLAW is an abbreviation for Control LAW. In short, the pilot has long since stopped pulling the joystick on the control cables, but only hints to the computer what he would like to learn in return, and the computer, in accordance with the CLAW embedded in it, already gives commands to various actuators.
What is it, why is it needed and how does it work, you can read hereThe test pilot there explains it very clearly.
Now a little about weight sensors
The WoW weight sensors are one of the components of the F-35A flight control system. They are mounted on the landing gear shock absorber, the main landing gear has two sensors, and the nose gear has one sensor. The control system is duplicated, so if several sensors fail, the system continues to operate. When the shock absorbers are completely relaxed and then compressed under the weight of the aircraft, the sensors determine that the aircraft is on the ground. The sensors are plunger-type; in the photo, you can see a wheel located in a recess. Although physical contact is required to trigger the sensor, this is not a microswitch, but a contactless sensor based on the Hall effect. That is, the plunger is retracted, approaches the sensing element, and we receive an ON signal. For precise operation, a certain distance must be maintained between the metal surface and the sensing element.
Four sensors from the accident aircraft were tested at the Air Force Research Laboratory and were found to be working reliably, all within specification. However, the specification does not address whether the sensors can operate as expected if the shock absorber does not fully extend due to ice in the shock absorber system.
The document then moves on to the CLAW control laws and flight control system.
Actually, here everything can be stated very briefly: due to incorrect operation of the weight sensors, caused by the nose landing gear wheel turning and not fully extending, which was due to ice forming in the hydraulic fluid, which was due to… etc., one thing leads to another. As a result, the aircraft computer selected the OG CLAW – On the Ground control law. This law is selected if three of the five weight sensors responded, indicating the presence of weight on the wheel.
Note. I can't believe that such an important decision for the aircraft is made based on the readings of three sensors. Perhaps the document does not name all the conditions for selecting the "on the ground" mode, there should be more. They simply must be there. For example, reducing the speed of the aircraft, because it begins to brake. And the throttle control handle should also be involved in this. Releasing the brake parachute... although the F-35 does not have them, but in principle? In the end, there may also be a simple mechanical toggle switch that the pilot switches to the "I landed" position. Oh well.
The document then goes on to provide information about the pilot's qualifications, his medical history, the weather, and other things that are no longer of interest. The pilot is said to have logged 2700 total flight hours, 554 of which were in the F-35A, and to have been qualified as a "pilot examiner."
Finally, final conclusion Chairman of the Investigation Committee, Colonel MICHAEL B. LEWIS
In forming my opinion, I relied on data from the Logistics Information System, black box data, the MA and MW pilot helmet-mounted display memory module, the cockpit panoramic display memory, MW pilot infrared sight data, analyses and reports from the Research Laboratory, and interviews with participants in the events.
Note: I will now omit what we have already learned and what the colonel repeats again. Here is what is interesting:
Because the flight director ordered the pilot to re-extend the landing gear after the first touchdown, ice also formed on the right main landing gear and prevented it from fully extending.
According to Lockheed Martin, if the control law is selected "on the ground" but the aircraft is in the air, it becomes uncontrollable.
Due to the lack of precise documentation, I have been unable to determine exactly when the water entered the landing gear. Based on interviews, I believe the likely cause was a drum of hydraulic fluid that had been with the squadron in Japan.
I find the following significant contributing factors leading to the accident: crew decision making, lack of squadron management control over handling of hazardous materials, and failure to follow hydraulic equipment maintenance procedures.
All involved in this incident – the MA and MW pilots, the controllers, the senior duty officer, and Lockheed experts – handled a complex situation with excellence, which had never happened before to any F-35. The MP pilot utilized various available resources to troubleshoot the problem and attempted to land the aircraft safely. The MW pilot took the initiative, and thanks to his accurate and timely observations, it was possible to assess how offset the nose gear of the accident aircraft was. The flight safety inspector, Lockheed Martin engineers, and 354th Squadron leadership assisted and provided their best advice. However, in this situation, the decision to advise the MP pilot to perform a touch-and-go landing resulted in his uncontrolled ejection. As demonstrated in the February 35, 6 F-2025A incident, in a similar situation, a pilot was able to land safely with the nose gear offset 10 degrees from center, without the pilot even realizing it. On the second approach on January 28, the nose gear of the accident aircraft remained offset 6 degrees left of center, which, based on the experience gained during the flight on February 6, would have allowed for a safe landing.
When the MP pilot transmitted the HRCS codes after the first landing attempt, conference participants might have recalled a Lockheed Martin maintenance circular from April 2024 that stated that weight sensor failures could lead to controllability issues. Had that been taken into account, the conference likely would have advised making the proposed abort landing or controlled ejection rather than attempting a second touch-and-go.
Note: Controlled and uncontrolled – probably means that the ejection occurred under less than favorable conditions: low altitude, large bank, and all that.
Next comes the reprimands of the technical service that failed to ensure the tightness of the oil barrel, and of the managers who allowed this to happen.
This is where the report ends. The report does not make any recommendations for changes in light of the lessons learned from the incident. And there are and will be other air forces that will have to use the F-35 in low temperatures. For example, Canada or Finland. But that is up to them.
In conclusion, a few comments from American readers:
planterfish
No aircraft is immune to poor maintenance.
crane
It appears that this piece of software does not take into account the altitude at which the airbase is located.
planterfish
Believe it or not, there are many bases located above sea level, some at several thousand feet. And pilots/staff are notoriously prone to making mistakes, even more so than WoW sensors.
jetcal1
When servicing hydraulic systems, any remaining fluid in the tank can become hazardous waste. Opening cans of oil or hydraulic fluid is strictly prohibited. Self-filling under its own weight directly from the can is also a big problem. Where was the person in charge?
Alaskatoy
Typically you service it with a MULE (Multi-purpose Utility Logistics Equipment, a small self-propelled cart) or a hydro cart (mobile source of hydraulic power, replaces the onboard system of the aircraft if necessary), both systems are closed. Every time we added fluid to it, we sent it for testing before we used it. There are also periodic checks, weekly and monthly. None of the hydraulic systems are protected from the elements, and they are all traditionally under a roof.
When I was a crew chief on the F-16 and F-22, we rarely serviced the landing gears with enough fluid to contaminate them with water unless they were sent to a repair shop for rebuild (I doubt that's possible on these new planes). During reconfiguration (?? I don't know what that is) the weight required nitrogen so fluid could sit in those gears for a long time, and it was probably their first cold winter (I'm in Anchorage). I'd like to look at the maintenance records and see if any of them ever actually serviced the hydraulics on these machines.
Zonker Harris
Press 1 if this is an emergency.
Press 2 if you would like to order parts for your F-35.
Press 3 if you know where the parts you need are.
Press 4 if you need anything else. Your wait time is 21 minutes, and you are 12th in line. Please stay in touch and take a short survey about our service quality.
Goyohi
I remember taking off and not hearing the WoW relay go off. This little relay is responsible for a huge number of functions: fuel consumption calculation, refueling alarms at the destination, pressure issues...
harbinger
How did Martin-Baker work?
Goyohi
Lots of malfunction messages. Dropped landing gear and landed.
No aircraft is immune to poor maintenance.
crane
It appears that this piece of software does not take into account the altitude at which the airbase is located.
planterfish
Believe it or not, there are many bases located above sea level, some at several thousand feet. And pilots/staff are notoriously prone to making mistakes, even more so than WoW sensors.
jetcal1
When servicing hydraulic systems, any remaining fluid in the tank can become hazardous waste. Opening cans of oil or hydraulic fluid is strictly prohibited. Self-filling under its own weight directly from the can is also a big problem. Where was the person in charge?
Alaskatoy
Typically you service it with a MULE (Multi-purpose Utility Logistics Equipment, a small self-propelled cart) or a hydro cart (mobile source of hydraulic power, replaces the onboard system of the aircraft if necessary), both systems are closed. Every time we added fluid to it, we sent it for testing before we used it. There are also periodic checks, weekly and monthly. None of the hydraulic systems are protected from the elements, and they are all traditionally under a roof.
When I was a crew chief on the F-16 and F-22, we rarely serviced the landing gears with enough fluid to contaminate them with water unless they were sent to a repair shop for rebuild (I doubt that's possible on these new planes). During reconfiguration (?? I don't know what that is) the weight required nitrogen so fluid could sit in those gears for a long time, and it was probably their first cold winter (I'm in Anchorage). I'd like to look at the maintenance records and see if any of them ever actually serviced the hydraulics on these machines.
Zonker Harris
Press 1 if this is an emergency.
Press 2 if you would like to order parts for your F-35.
Press 3 if you know where the parts you need are.
Press 4 if you need anything else. Your wait time is 21 minutes, and you are 12th in line. Please stay in touch and take a short survey about our service quality.
Goyohi
I remember taking off and not hearing the WoW relay go off. This little relay is responsible for a huge number of functions: fuel consumption calculation, refueling alarms at the destination, pressure issues...
harbinger
How did Martin-Baker work?
Goyohi
Lots of malfunction messages. Dropped landing gear and landed.
That's all for now. Thank you for your attention.
Information