USN T-45 Grounded After Pilots Strike
Thread Starter
LOX or OBOGS? T-45 Grounding, USN
The new tech appears to have some bugs in it, "new" being only about 25 years old.
Military: The Intel - San Diego Union Tribune
The T-45 (Goshawk) fleet is grounded for a while due to safety concerns over the crew oxygen system. It appears that a few IPs are speaking out of school.
I know that quite a few jets use the OBOGS system ... wonder if the grounding is universal or TMS dependent.
Military: The Intel - San Diego Union Tribune
The T-45 (Goshawk) fleet is grounded for a while due to safety concerns over the crew oxygen system. It appears that a few IPs are speaking out of school.
I know that quite a few jets use the OBOGS system ... wonder if the grounding is universal or TMS dependent.
Last edited by Lonewolf_50; 6th Apr 2017 at 17:17.
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I'll have to find out what 'TMS' means (is it like PMS?) but anyways over the last few years there have been many articles about the 'hypoxia/OBOGS' & pressurization problems in the Hornet / Super Hornet fleet that have been very difficult to diagnose and fix with what to me looks like a lot of effort from the USN. Special rigs give USN 'hornet' pilots hypoxia symptom training. I could give plenty of URLs for readers if required. I'm a vet of the LOX 'pure oxygen under pressure' era which had its own problems such as "acceleration atelectasis".
Last edited by SpazSinbad; 5th Apr 2017 at 21:24. Reason: vid
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Way back when A-4 pilots sucked pure oxygen under pressure from their masks (one had to get used to opening the mouth with outward pressure to resist the inward pressure of the LOX coming down). Valsalva Maneuver anyone? Buehler? Anyone? Best let medicos explain:
AP Impact: Air Force insiders foresaw F-22 woes 27 Sep 2012
Physiology of Flight
"...Another oxygen effect which may be loosely grouped under the general heading of oxygen toxicity is atelectasis while breathing 100 percent oxygen during + Gz acceleration, although the term “oxygen toxicity” in this context is a misnomer. Acceleration atelectasis is included in this section only because it occurs when an aviator is breathing 100 percent oxygen. The primary factor responsible for the atelectasis is probably the complete cessation of basilar alveolar ventilation under acceleration. There is also markedly increased blood flow to the basilar alveoli as opposed to the apical ones, along with a reduction in basilar alveolar volumes as the weight of the lung under acceleration compresses the bases against the diaphragm. With these factors acting in concert, and when the alveoli in question contain only oxygen, water vapor, and carbon dioxide, oxygen absorption (the main cause of acceleration atelectasis) leads to alveolar collapse, and atelectasis can occur very rapidly.
If nitrogen is present in the inspired gas, the gas absorption and consequent alveolar collapse are greatly slowed. The time required for complete absorption of gas contained in the lower quarter of the unventilated lung, with normal blood flow distribution, is increased from five minutes on 100 percent oxygen to about 25 minutes on 50 percent oxygen, 50 percent nitrogen. In addition, there is evidence that nitrogen in the lung acts as a “spring” by preventing alveolar collapse when all the oxygen is absorbed.
Pulmonary atelectasis during flight may result in several performance-degrading effects, including distracting or perhaps even incapacitating cough and chest pain and arterial hypoxia due to the shunt of venous blood through the nonaerated alveoli. The Flight Surgeon should remain aware that coughing, substernal pain, and decreased altitude tolerance may indicate the development of this condition. In any event, acceleration atelectasis usually resolves itself in a few days with little or no treatment...." http://www.operationalmedicine.org/T...eonsManual.pdf
"...Another oxygen effect which may be loosely grouped under the general heading of oxygen toxicity is atelectasis while breathing 100 percent oxygen during + Gz acceleration, although the term “oxygen toxicity” in this context is a misnomer. Acceleration atelectasis is included in this section only because it occurs when an aviator is breathing 100 percent oxygen. The primary factor responsible for the atelectasis is probably the complete cessation of basilar alveolar ventilation under acceleration. There is also markedly increased blood flow to the basilar alveoli as opposed to the apical ones, along with a reduction in basilar alveolar volumes as the weight of the lung under acceleration compresses the bases against the diaphragm. With these factors acting in concert, and when the alveoli in question contain only oxygen, water vapor, and carbon dioxide, oxygen absorption (the main cause of acceleration atelectasis) leads to alveolar collapse, and atelectasis can occur very rapidly.
If nitrogen is present in the inspired gas, the gas absorption and consequent alveolar collapse are greatly slowed. The time required for complete absorption of gas contained in the lower quarter of the unventilated lung, with normal blood flow distribution, is increased from five minutes on 100 percent oxygen to about 25 minutes on 50 percent oxygen, 50 percent nitrogen. In addition, there is evidence that nitrogen in the lung acts as a “spring” by preventing alveolar collapse when all the oxygen is absorbed.
Pulmonary atelectasis during flight may result in several performance-degrading effects, including distracting or perhaps even incapacitating cough and chest pain and arterial hypoxia due to the shunt of venous blood through the nonaerated alveoli. The Flight Surgeon should remain aware that coughing, substernal pain, and decreased altitude tolerance may indicate the development of this condition. In any event, acceleration atelectasis usually resolves itself in a few days with little or no treatment...." http://www.operationalmedicine.org/T...eonsManual.pdf
“...The group [RAW-G] was founded by members of the F-22 community who were concerned about how the unique demands of the aircraft could affect pilots. The fighter can evade radar and fly faster than sound without using afterburners, capabilities unmatched by any other country. It also flies higher than its predecessors and has a self-contained oxygen generation system to protect pilots from chemical or biological attack....
...By the time RAW-G got going, some pilots were already experiencing a problem called "Raptor cough" — fits of chest pain and coughing dating back to 2000 that stem from the collapse of overworked air sacs in the lungs.
The group concluded that the F-22's On-Board Oxygen Generation System — or OBOGS — was giving pilots too much oxygen, causing the coughing. The more often and higher the pilots flew after being oxygen-saturated, group members believed, the more vulnerable pilots affected by the condition would be to other physiological incidents.
RAW-G recommended more tests and that the F-22's oxygen delivery system be adjusted through a digital controller and a software upgrade.
"The schedule would provide less oxygen at lower altitudes than the current schedule, which has been known to cause problems with delayed ear blocks and acceleration atelectasis," the technical term for the condition that leads to the coughing, according to the minutes from RAW-G's final meeting....” http://www.rdmag.com/news/2012/09/ap...saw-f-22-woes/
...By the time RAW-G got going, some pilots were already experiencing a problem called "Raptor cough" — fits of chest pain and coughing dating back to 2000 that stem from the collapse of overworked air sacs in the lungs.
The group concluded that the F-22's On-Board Oxygen Generation System — or OBOGS — was giving pilots too much oxygen, causing the coughing. The more often and higher the pilots flew after being oxygen-saturated, group members believed, the more vulnerable pilots affected by the condition would be to other physiological incidents.
RAW-G recommended more tests and that the F-22's oxygen delivery system be adjusted through a digital controller and a software upgrade.
"The schedule would provide less oxygen at lower altitudes than the current schedule, which has been known to cause problems with delayed ear blocks and acceleration atelectasis," the technical term for the condition that leads to the coughing, according to the minutes from RAW-G's final meeting....” http://www.rdmag.com/news/2012/09/ap...saw-f-22-woes/
Last edited by SpazSinbad; 5th Apr 2017 at 23:33. Reason: cough cough
Salute!
Yeah, Spaz, I flew with the O2 under pressure in the VooDoo. Guess they were thinking we could zoom way up and survive a little bit bove 50,000 feet without spacesuits when doing a snap up versus a target at 70,000 + feet. We were pressurized, but guess they were worried it might fail.
Then the delayed ear blocks we learned to clear when sleeping was the best trick I learned. We also had something like the Raptor Cough but we never pulled sustained gees and certainly nothing above 4 or 5 gees for more than a few seconds.
I question the assertion that OBOGS defeats chem warfare, as tanked oxygen is guaranteed not to become contaminated.
As Wolf has noted, the technology is old. We tested a few jets at Hill in early 80's. My theory is HHQ folks wanted quicker turns and less dependence upon ground equipment and all the stuff required for LOX. Due to my corroded lungs, I use both portable and home model concentrators. They provide 95% O2 up to 10,000 feet, then fall off. I haven't heard of histotoxic hypoxia with those machines.
I wonder why we can't have sensors in the system to detect harmful gases or even particles. That won't prevent the high gee and pure oxygen problems, but it would sure as hell let the pilot/crew know their system was porked.
Gums sends...
Yeah, Spaz, I flew with the O2 under pressure in the VooDoo. Guess they were thinking we could zoom way up and survive a little bit bove 50,000 feet without spacesuits when doing a snap up versus a target at 70,000 + feet. We were pressurized, but guess they were worried it might fail.
Then the delayed ear blocks we learned to clear when sleeping was the best trick I learned. We also had something like the Raptor Cough but we never pulled sustained gees and certainly nothing above 4 or 5 gees for more than a few seconds.
I question the assertion that OBOGS defeats chem warfare, as tanked oxygen is guaranteed not to become contaminated.
As Wolf has noted, the technology is old. We tested a few jets at Hill in early 80's. My theory is HHQ folks wanted quicker turns and less dependence upon ground equipment and all the stuff required for LOX. Due to my corroded lungs, I use both portable and home model concentrators. They provide 95% O2 up to 10,000 feet, then fall off. I haven't heard of histotoxic hypoxia with those machines.
I wonder why we can't have sensors in the system to detect harmful gases or even particles. That won't prevent the high gee and pure oxygen problems, but it would sure as hell let the pilot/crew know their system was porked.
Gums sends...
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Gums, A4G pilots could be identified in the Nowra Mess by their constant Valsalva Maneuvering. Waking up with painful ears could be no joke but cleared by above. I was not particularly bothered by low altitude high G 'coughs' however one pilot was severely affected, causing our new flying doctor (qualified on A4Gs) to investigate, giving us a heap of info. When that pilot died in a TA4G crash into the sea in 1974 that 'cough' - as a cause - was investigated but discounted. RIP
The Kiwis had LOX in their original A-4Ks but at some time (maybe KAHU upgrade?) changed to a cabin air/oxygen combo - much like the Sea Venom/Vampire or Macchi MB326H.
The Kiwis had LOX in their original A-4Ks but at some time (maybe KAHU upgrade?) changed to a cabin air/oxygen combo - much like the Sea Venom/Vampire or Macchi MB326H.
Ecce Homo! Loquitur...
USN T-45 Grounded After Pilots Strike
Navy Announces Three-Day Grounding for T-45s After Pilot Strike | Military.com
Are they civil instructors?
Are they civil instructors?
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A new hint of the GrowlingShornet struggles with OBOGS: 06 Apr 2017
"...Hypoxia has plagued the Navy’s T-45s and larger fleet of F/A-18 fleet for years now, but the issue has recently received more attention on Capitol Hill. During a 28 March House Armed Services Committee hearing, members of Congress expressed concern over dangerous crew cabin pressure in the older Super Hornets and possible oxygen contamination in the newer F/A-18 variants. The F/A-18A through D models saw a 90% increase in physiological episodes (PEs) over the last fiscal year, while the E and F models saw an 11% increase in the same period. Meanwhile, the EA-18G doubled its number of PEs during that same time."
https://www.flightglobal.com/news/ar...-fleet-435958/
https://www.flightglobal.com/news/ar...-fleet-435958/
Fun Fact: there is a Lt Michael Pence in USN training program, either student or IP. I think thus making headlines is the reason for the grounding.
GF
GF
Thread Starter
Long running OBOGS issues: got it.
Contamination: got it.
@Spazsinbad: TMS ~ Type/Model/Series. Sorry, lapsed into old USN Acronym-speak.
Did someone change a vendor, or a parts supplier, or make an airframe mod?
Is this the usual "we can never get any spare parts to fix the damned things properly" that happens in various budgetary cycles? I only had two experiences with OBOGS, both in a T-45, my other O2 was with a mixer or diluter with the chance to go 100 full )2 for emergencies. (LOX or other O2 bottles, model dependent).
This isn't new technology: why is this not fixed? I think that's what has the pilots frustrated. It also, apparently, is not a new problem. Heard rumor that an ejection last year was due to OBOGS malfunction. Will try to find a link.
Contamination: got it.
@Spazsinbad: TMS ~ Type/Model/Series. Sorry, lapsed into old USN Acronym-speak.
Did someone change a vendor, or a parts supplier, or make an airframe mod?
Is this the usual "we can never get any spare parts to fix the damned things properly" that happens in various budgetary cycles? I only had two experiences with OBOGS, both in a T-45, my other O2 was with a mixer or diluter with the chance to go 100 full )2 for emergencies. (LOX or other O2 bottles, model dependent).
This isn't new technology: why is this not fixed? I think that's what has the pilots frustrated. It also, apparently, is not a new problem. Heard rumor that an ejection last year was due to OBOGS malfunction. Will try to find a link.
Student I think and I would hardly think that has as much new-worthiness as IP's refusing to fly. There must be a very good Naval airman in the leadership to take seriously the word of those IP's over the "Navy line." Every now and then...and that's real good news.
Ecce Homo! Loquitur...
Galaxy, in my link above.
"News of the pilots' refusal to fly was first reported Tuesday night by Fox News. The outlet reported that Marine 1st Lt. Michael Pence, son of Vice President Mike Pence, is among the student pilots affected by the strike."
Lone wolf, same link.
"Fox reported that physiological episodes connected to problems with the trainers' onboard oxygen generation systems had quadrupled over the last five years, with 10 episodes in the last month. In August, the report notes, a flight instructor and student ejected near Kingsville after they both felt symptoms of hypoxia. While they both survived without injury, the aircraft crashed and was destroyed."
"News of the pilots' refusal to fly was first reported Tuesday night by Fox News. The outlet reported that Marine 1st Lt. Michael Pence, son of Vice President Mike Pence, is among the student pilots affected by the strike."
Lone wolf, same link.
"Fox reported that physiological episodes connected to problems with the trainers' onboard oxygen generation systems had quadrupled over the last five years, with 10 episodes in the last month. In August, the report notes, a flight instructor and student ejected near Kingsville after they both felt symptoms of hypoxia. While they both survived without injury, the aircraft crashed and was destroyed."
Thread Starter
ORAC: To answer your question, no, the Navy instructors who fly the T-45 are not civilians.
(The simulator instructors are civilian contractors, however, a great many of them being former military pilots).
(The simulator instructors are civilian contractors, however, a great many of them being former military pilots).
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During two thread amalgamation this info about the NAVY instructors from the original article cited by all other articles was lost:
"EXCLUSIVE: More than 100 U.S. Navy instructor pilots are refusing to fly in protest of what they say is the refusal of top brass to adequately address an urgent problem with training jets’ oxygen system, multiple instructor pilots tell Fox News. The boycott started late last week and has effectively grounded hundreds of training flights. “The pilots don’t feel safe flying this aircraft,” one instructor pilot told Fox News...."
Navy instructor pilots refusing to fly over safety concerns; Pence's son affected | Fox News
Navy instructor pilots refusing to fly over safety concerns; Pence's son affected | Fox News
'Raptor cough'? That sounds rather similar to 'Hunter Lung', about which all RAF trainee pilots were taught at AMTC North Luffenham several years ago...
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I wonder if Lt Pence would avoid the draft if WW3 broke out today, as is recent tradition in US politics.
The honourable Senator McCain (though he's "not a hero" because he got shot down according to one retard), George Bush Senior (who I believe also got shot down in WW2), JFK and John Kerry deserve special mention and respect among others. All seemed to change in the 60's/ 70's. George W and D Trump spring to mind but I'm sure there were many many others who received "special" consideration due to family "connections"...
The honourable Senator McCain (though he's "not a hero" because he got shot down according to one retard), George Bush Senior (who I believe also got shot down in WW2), JFK and John Kerry deserve special mention and respect among others. All seemed to change in the 60's/ 70's. George W and D Trump spring to mind but I'm sure there were many many others who received "special" consideration due to family "connections"...
Last edited by Octane; 7th Apr 2017 at 10:56.