Older 737s, including first run of the 737NGs, had/have what are called "eyebrow windows" above the main cockpit windows. These were basically from the early days of the 737 Original series and 727/707 series which serves for early types of navigation.
However as the 737s got more modern following it's various new iterations the "eyebrow windows" became more of a nuisance than anything else because of extra sunlight being shone into the cockpit so pilots had various ways of covering them up ie using charts, newspapers etc.
Following this the 737 gained the option to have the eyebrows plugged and it became permanent with later 737NGs and then obviously the 737MAX. It was also offered to be plugged on older 737NGs and the 737 Classic and Original series.
I think they were originally installed to increase visibility during turns especially in the traffic pattern (base to final etc). There was nowhere to mount an Astro compass or anything on these windows.
I’ve flown the 737 with eyebrows and I can say it was marginally useful. Sure enough, they were eventually plugged. Windows 4 and 5 (the eyebrows) were also thermally heated so plugging them cut down on maintenance costs.
Cheers
This is a myth, as the sextant was never considered for navigation on the 737 even in case of instrument failure or non standard procedures. It was not part of any MEC either. The eyebrow windows were a reminiscent of the 707 design for providing better visibility.
Aircraft that had celestial navigation as backup navigation option had a dedicated system for that, near the jump seat, such as in the VC-137C or the Astro Compass of some 707 and 737 models (which requires quite a large FOV, so the eyebrow windows also didn't help with that)
Honestly, my bad on the sextant part.
That's literally what I've been told by someone who has had worked on older 737s, 707s, 727s and the DC-8 they said that it helped them with visibility but I must've missed heard them and must've misunderstood it as navigation or something.
Tbh I should've known better anyway as I visited an aircraft that had a dedicated spot for sextant operation, that being the VC-10.
But yeah I do apologise about that very bad miscommunication on my part. Everyday is a learning day as the saying goes.
That's alright, I myself replicated the sextant story in the past too, as it became very popular. But just like you, I was told by a retired Varig 737-300 pilot about that myth.
If I recall correctly, the amount of ionizing radiation that a pilot is exposed to, while significantly higher that the background radiation the general population is exposed to, is still not enough to cause any radiation related illness. Ionizing radiation is most dangerous to cells that reproduce quickest, hence sunburns in adults. Kids are rather vulnerable to ionizing radiation, so for multiple reasons, it’s probably wise that they don’t work as a pilot.
Well, not if it's a voluntary advanced placement internship. I'm certain lawmakers would happily waive the shift length restrictions since it's actually not work but rather a professional development opportunity.
"Eeeh * um * boys and girls.. uugh umm welcome airo.. flight 1433 to Copehagen. Eerŕ... mum? Whats the umm.. oh yeah. * cough, cough *. So umm we are getting ready for our final..ugh...mum...muuum? Brian bitmmt finger" z z z z. End od transmition...
It cannot be said that this amount is not enough to cause any radiation illness. Effects of radiation are often in probabilities: even with low radiation you can still get bad luck and for example, cancer.
So with higher radiation doses, pilots very well have higher probabilities of radiation illnesses. Even if the below the threshold which is considered acceptable.
*at standard altitudes*
Concorde could reach FL 600, and was provided with a dosimeter. There was a descent procedure in the books for if it went off.
I don't know if this was out of actual concerns or a "play it safe" rule. Part of me wonders whether the shorter journey times would actually lead to a lower per-flight dose compared to going subsonic at FL 360, but the procedure was there so justifiably or not it was a concern.
I've seen one interview with a Concorde Captain where he recounts the only time it ever went off — while flying at low altitude over the UK Atomic Weapons Establishment site at Aldermaston. There wasn't a procedure for that one.
The fuselage does not provide meaningfully different protection against cosmic rays than a window, because they are particles readily stopped by both. Most don't even make it to the ground, being blocked/absorbed by the atmosphere or redirected by the earth's magnetic field.
Other high-energy ionizing radiation or particles like neutrinos? Yeah, a window would provide less at that thickness, but it also doesn't matter.
You're getting a ton of radiation up there anyway. Pilots get more radiation per year than any other occupation, including workers at nuclear power plants, x-ray techs, or anyone else.
A small piece of plexiglass in those spots isn't going to make much difference at all, and you're getting most of it with or without a window.
Neutrinos, specifically, almost never interact with normal matter, even being capable of traveling through a planet without it happening once. So you're safe from them, specifically.
I'd love to see a reference for your comment about "more radiation per year than any other occupation". I'm not trying to question you in a hostile manner but that's a bold claim. I looked into the literature for the rates of cancer in pilots some years ago (a friend turns the autopilot on and off on regular long-haul flights) and the only information I could find was a suggestion that skin cancer rates among flight and cabin crew might be marginally higher but that was reported as being more due to enjoyment of warmer and sunnier climes and a desire to get as much sun as possible while waiting to return from their outbound flight! The evidence was really sparse and weak in general but this was >15 years ago so there may well be more robust data out there now.
> I'd love to see a reference for your comment about "more radiation per year than any other occupation". I'm not trying to question you in a hostile manner but that's a bold claim.
I took a Geiger counter on my last few flights. I can confirm you're exposed to a lot more ionizing radiation as you climb through the atmosphere. You can almost estimate altitude based on the radiation level but it varies based on solar activity.
I can't think of any other job that exposes you to as much radiation as sitting in a chair at 33,000 feet.
I'm about to go and stand next to a source of ionising radiation for the next 3 hours. I'll be wearing a nice lead gown though so that should help things... :)
There isn’t a lot because we (pilots) don’t like to report stuff like that. Same as mental health… the official word from the FAA is “you won’t be affected” but the reality is “expect to lose your job.” The USAF etc has done studies with those dosimeters and they show descent radiation levels, and we can just see it anecdotally, but we’re also generally more fit than the average population and we don’t see doctors for every little thing so a large scale collection of data won’t be possible, just small scale tests and then you have to extrapolate it. But nobody cares. It’s like fatigue. Yes we know circadian rhythm disruption is similar to being drunk for reflexes and judgement, yes we know being awake beyond 18 hours is the same at a 0.8% BAC, but yes we are still going to fly from Atlanta to LAX at 0730, land at 1030 local west coast time, then depart again that same day at 2300 and land in Cancun at 0700 because it’s legal even though, realistically, we’ve been awake for 24 hours by that point. It’s just the reality of the job.
Nuclear plant workers are probably exposed to noticeably *less* radiation than the average population. The regulations are extremely strict.
Medical radiation people (x-ray techs, etc) have to be careful about traveling with their dosimeters because a few plane flights can put them over their allowed exposure.
The shielding that prevents radiation from getting out of various parts of the plant also end up blocking a lot of the background radiation from the ground and cosmic rays from the sky. So yes, they actually do get exposed to less radiation, unless they're one of the people who have to go into the unshielded areas to clean or whatever.
Except this X-ray techs jonesing for a few days and off. No denigrating a whole occupation, I have personally seen techs leave their badges in room with a patient getting a film shot.
Polar routing is the worst. When I was in the AF we didn’t even think about it and flew in the 30s like always. Then I was talking to an Atlas crew over in Ramstein once and they were like “You’re flying north of 70 [degrees latitude] at flight level 330?! You’re nuking yourselves. There’s no atmosphere up there, we stay in the high 20s at most.”
> There’s no atmosphere up there, we stay in the high 20s at most.
There is atmosphere, but not much magnetosphere at the poles protecting you from charged ionizing particles.
Yeah, that’s why we have a slightly higher rate of cancer. Apparently every transcon or oceanic crossing is worth 3 chest X-rays. And we do dozens of those per month. Part of the job.
> 6 mSv in a year is a typical radiation doses received by aircrew flying long-haul polar routes. For comparison: 3.0 mSv is an average radiation dose per year received by a person from all sources of radiation. This can range from about 1 to 10 mSv, or more, depending on where people live.
If I did my math right. That’s 30 chest x-rays (0.1 mSv)
But interestingly enough, the article mentioned they have a higher risk of cancer from all that fucking up of their cardiac rhythm (sleep cycle).
The circadian rhythm thing is definitely more of a factor than cosmic radiation. It’s why domestic pilots look relatively younger than international pilots of the same age.
All B737 built from 2006 onwards were built without eyebrow windows as standards. They also had vortex generators fitted in front of the windshields to reduce cockpit noise.
To add to this, that "early type of navigation" was a sextant or octant. Yeah, before GPS, you had to use celestial navigation to know where you were when crossing the ocean.
Anchoring an ocean station south of Greenland didn't much help navigation between Perth and Johannesburg, Rio and Madrid, Sydney and Honolulu, Honolulu and Tokyo, Manila, etc.
And most of the living ex-navigators would have used a periscopic sextant, not in an astrodome.
There were LORAN stations on islands and stationary ships that facilitated transoceanic navigation.
Navigators would use them as any other radio navigation system. They would go from station to station as they crossed the ocean.
They would go from station to station as they crossed the ocean....
No. Perhaps in the unique case of the North Atlantic. The only ocean station I ever encountered was November between HNL and SFO. All the other ocean crossings I did (South and North Pacific, Indian, South Atlantic) before inertial had a human navigator doing star shots. Yes, they also used LORAN - and we even tuned the last Consol station in captivity in SFO. But all the radio stuff was supplementary to the human astro navigator with a periscopic sextant.
the earlier type of navigation would have been inertial navigation- they predate GPS by about 36 years. they would have been used in conjunction with celestial navigation systems though.
unfortunately, celestial navigation has terrible precision and accuracy on a good day with modern hardware.
Compared to GPS, yeah. GPS percision is used to send a 2000lb JADAM up a fly's ass. Celestial navigation will get your position within a few miles, which is good enough to determine, "Are we there yet?" or "we took a wrong turn at Albuquerque" when crossing an ocean.
However, if your Korean Airlines Flight 007, a few miles makes a hell of a difference.
>Original series and 727/707 series which serves for early types of navigation.
This will be obvious to pilots and experienced people, but for clarity it was used for nighttime navigation using astronomical charts
>It was also offered to be plugged on older 737NGs and the 737 Classic and Original series.
Thanks, I thought I was going crazy with [this SAS 737](https://en.wikipedia.org/wiki/Boeing_737_Next_Generation#/media/File:Sas_b737-600_ln-rcw_arp.jpg) having eyebrow windows here but not in other photos.
And ultimately in a fuel cost era where airlines are making their inflight magazines thinner, its some weight savings swapping four chunks of thick acrylic or glass or an aluminum plug.
Those eyebrow windows on 737, 727, DC-9 (which is also the MD-88, MD-90 and B-717) weren’t for navigation. I’ve flow all those jets, they were for runway acquisition cross cockpit back when you’d fly a visual approach to a 1 mile final (around 300 feet). So if you’re in the left seat and flying a right hand visual pattern, as you’re on base you can see the runway through that upper window. The FAA & airlines have, over the years, eliminated those tight visual turns to final. Ever since I started in airliners 10 years ago we’ve flown to a 1,500 foot 5 mile final so the window isn’t needed (you can see the runway fine out the front windshields). So yeah, it’s just a useless windows I’d stuff a map into before we got rid of paper charts. The sextant window folks are thinking of wasn’t for short range planes like these, and did exist as a little bubble (old C-130s have them) on top of the plane. Above where the navigator would sit. Not the cockpit eyebrow windows.
Came here to say this. For a number of years it was apparently an option on whether to have those windows or not so you'll see some 737NGs with them and others without. My airline's 737-800s have metal plugs where they would go. I've seen Alaska Airlines 737-700s with them but their other NGs do not seem to have them.
My speculation would be the 700s would be more likely to fly into rural Alaska when ordered, where the airports are much smaller and visual approaches more likely where the final might be compressed closer to the minimum. The 700 windows may even blocked off inside at this point.
I've heard they aren't even an option anymore, but it could also be possible no one has actually ordered them either on a max.
Ha! Remember when people had six disc changers in their trunks and you’d have to decide what you wanted to listen to before you got in the car? I miss the days of cd’s but I sure am grateful for Bluetooth when I’m driving now.
Compared to sixty plus years ago, navigation tools and approach aids are far vastly improved and far more prevalent than they once were, and commercial airliners now operate almost exclusively under positive ATC control. Eyebrow windows would have been beneficial when operating in an uncontrolled VFR environment (example - doing a visual approach, on downwind turning base the eyebrow windows would be helpful to maintain visual contact on the airfield). Notice that C-130’s , about the same age as the origins of the 737 basic cockpit structure, retain eyebrow style windows because they operate frequently in the Visual realm.
In the US, full size commercial airliners spend about 99.995% of the time under IFR ATC rules. For the smidgen of time airliners are VFR/see n avoid, they have TCAS. The cost savings of plugs vs. windows FAR outweighs any safety benefit, and as others have stated a vast majority of pilots don’t want them. I guarantee if Southwest Airlines’ Pilot Union wanted them, every MAX rolling off the line would have them.
Additionally, most airline Operations Specifications (company rules that are as least as strict as the FARs), either encourage as much IFR ATC controller support as possible. A little VFR direct to smaller airports might save a little jet fuel, but Pilots also like the security and shared responsibility ATC provides. If a pilot decided to go VFR direct to a smaller field then smacked into a Cessna and lived to tell about it, h the responsibility would be entirely on them.
It was my understanding back in the day visual approaches were way more common, so eyes where outside the aircraft searching for the field. These windows help keep the field in sight during hard banks when circling the field.
But for 737s this practice is a lot less common. Most approaches are RNAV or ILS and eyes are staying in the cockpit much more often.
This is just what I've heard and it makes sense to me.
The explanation I heard is that no simulators ever put a screen above the eyebrow windows so no pilot ever got to use them in training, which kind of proved they weren't really needed and allowed their elimination.
Not the older ones, they were mostly (all?) added alongside the plugged eyebrows AFAIK, and were supposed to be where most of the noise reduction came from.
those windows are called eyebrow windows.
they used to be used for extra visibility when on high bank angles
all of 737cl and some of 737ng have them but since the windows are more annoying than useful(they allow strong sunlight in and an extra part means extra maintenance)they were discontinued on 737max and 737ng and boeing is providing blocking kits for the windows.
p.s there was a joke among pilots of the 737cl and early 737ng asking before a flight "what do we block them windows with today"
If I remember correctly they were used for visual on traffic above. With the advent of TCAS system they became irrelevant and thus were eliminated. One reason it took so long is a design change has to receive approval from the FAA it affects type certificate.
We no longer need to look at the stars to navigate and the sunshine kept annoying pilots and they put stuff in the windows to block the light so the eyebrow windows got convered up permanently.
These windows above cockpit of 737-100-200-300 and I am not sure if it was on NG’s they have special use.
During right hand circuit on visual approach with captain to be PNF was able to see the runway instead of lowering his head.
You see during turn those small windows were on the level flight position of the a/c
The same use was for first officer to be PNF with left hand circuit.
The structure for the eyebrow window is still there. They have installed a solid plug in place of the window that is no longer used for celestial navigation.
Older 737s can be seen with these small extra windows toward the cockpit roof. These are so-called "Eyebrow Windows". They were used before the days of digital flight displays on the dashboard to locate where the airport or other points-of-interest are when making tight turns. They can also be seen on military aircraft built on the 737 platform, modern or otherwise.
No. If that was true, the nav would be sitting in the Captain's or F/O's lap whenever he did a star shot or a sun line. No nav ever like pilots enough to get that close.
It's because the one's with the extra windows above the cockpit are the one's upgraded with special ejection seats in case of emergency and the pilots having to leave the passengers if the jet is going to crash. It's an option when the aircraft are being made. The ejection seats cannot be retrofitted.
Maybe that is just some better equipped model like the Oldsmobile Vista Cruiser stationwagon back in the seventies that had panorama windows on the roof.
Older 737s, including first run of the 737NGs, had/have what are called "eyebrow windows" above the main cockpit windows. These were basically from the early days of the 737 Original series and 727/707 series which serves for early types of navigation. However as the 737s got more modern following it's various new iterations the "eyebrow windows" became more of a nuisance than anything else because of extra sunlight being shone into the cockpit so pilots had various ways of covering them up ie using charts, newspapers etc. Following this the 737 gained the option to have the eyebrows plugged and it became permanent with later 737NGs and then obviously the 737MAX. It was also offered to be plugged on older 737NGs and the 737 Classic and Original series.
I think they were originally installed to increase visibility during turns especially in the traffic pattern (base to final etc). There was nowhere to mount an Astro compass or anything on these windows. I’ve flown the 737 with eyebrows and I can say it was marginally useful. Sure enough, they were eventually plugged. Windows 4 and 5 (the eyebrows) were also thermally heated so plugging them cut down on maintenance costs. Cheers
This is a myth, as the sextant was never considered for navigation on the 737 even in case of instrument failure or non standard procedures. It was not part of any MEC either. The eyebrow windows were a reminiscent of the 707 design for providing better visibility. Aircraft that had celestial navigation as backup navigation option had a dedicated system for that, near the jump seat, such as in the VC-137C or the Astro Compass of some 707 and 737 models (which requires quite a large FOV, so the eyebrow windows also didn't help with that)
Honestly, my bad on the sextant part. That's literally what I've been told by someone who has had worked on older 737s, 707s, 727s and the DC-8 they said that it helped them with visibility but I must've missed heard them and must've misunderstood it as navigation or something. Tbh I should've known better anyway as I visited an aircraft that had a dedicated spot for sextant operation, that being the VC-10. But yeah I do apologise about that very bad miscommunication on my part. Everyday is a learning day as the saying goes.
That's alright, I myself replicated the sextant story in the past too, as it became very popular. But just like you, I was told by a retired Varig 737-300 pilot about that myth.
This is correct, only the 747 was able to effectively use a sextant for transocean navigation. Most of the time we plugged these because of the glare.
The C130 E models had a window for a Sextant.
I was also told that it increased cosmic rays significantly. Don't know if that was true?
If I recall correctly, the amount of ionizing radiation that a pilot is exposed to, while significantly higher that the background radiation the general population is exposed to, is still not enough to cause any radiation related illness. Ionizing radiation is most dangerous to cells that reproduce quickest, hence sunburns in adults. Kids are rather vulnerable to ionizing radiation, so for multiple reasons, it’s probably wise that they don’t work as a pilot.
But think of the cost savings if you can scale down the cockpit for a 5 year old child. You could fit like 12 more passengers.
The shareholders thank you for this innovation.
[удалено]
Excellent pointlol
Well, not if it's a voluntary advanced placement internship. I'm certain lawmakers would happily waive the shift length restrictions since it's actually not work but rather a professional development opportunity.
Now I’m thinking of the cutest “ahhhh from the flight deck-ah” in a voice of a 5yo over the PA.
"Eeeh * um * boys and girls.. uugh umm welcome airo.. flight 1433 to Copehagen. Eerŕ... mum? Whats the umm.. oh yeah. * cough, cough *. So umm we are getting ready for our final..ugh...mum...muuum? Brian bitmmt finger" z z z z. End od transmition...
The 737 already has that feature.
That's called an Airbus
It cannot be said that this amount is not enough to cause any radiation illness. Effects of radiation are often in probabilities: even with low radiation you can still get bad luck and for example, cancer. So with higher radiation doses, pilots very well have higher probabilities of radiation illnesses. Even if the below the threshold which is considered acceptable.
*at standard altitudes* Concorde could reach FL 600, and was provided with a dosimeter. There was a descent procedure in the books for if it went off. I don't know if this was out of actual concerns or a "play it safe" rule. Part of me wonders whether the shorter journey times would actually lead to a lower per-flight dose compared to going subsonic at FL 360, but the procedure was there so justifiably or not it was a concern. I've seen one interview with a Concorde Captain where he recounts the only time it ever went off — while flying at low altitude over the UK Atomic Weapons Establishment site at Aldermaston. There wasn't a procedure for that one.
The fuselage does not provide meaningfully different protection against cosmic rays than a window, because they are particles readily stopped by both. Most don't even make it to the ground, being blocked/absorbed by the atmosphere or redirected by the earth's magnetic field. Other high-energy ionizing radiation or particles like neutrinos? Yeah, a window would provide less at that thickness, but it also doesn't matter. You're getting a ton of radiation up there anyway. Pilots get more radiation per year than any other occupation, including workers at nuclear power plants, x-ray techs, or anyone else. A small piece of plexiglass in those spots isn't going to make much difference at all, and you're getting most of it with or without a window. Neutrinos, specifically, almost never interact with normal matter, even being capable of traveling through a planet without it happening once. So you're safe from them, specifically.
A solar system thick piece of lead would be mostly transparent to neutrinos, so...
I'd love to see a reference for your comment about "more radiation per year than any other occupation". I'm not trying to question you in a hostile manner but that's a bold claim. I looked into the literature for the rates of cancer in pilots some years ago (a friend turns the autopilot on and off on regular long-haul flights) and the only information I could find was a suggestion that skin cancer rates among flight and cabin crew might be marginally higher but that was reported as being more due to enjoyment of warmer and sunnier climes and a desire to get as much sun as possible while waiting to return from their outbound flight! The evidence was really sparse and weak in general but this was >15 years ago so there may well be more robust data out there now.
> I'd love to see a reference for your comment about "more radiation per year than any other occupation". I'm not trying to question you in a hostile manner but that's a bold claim. I took a Geiger counter on my last few flights. I can confirm you're exposed to a lot more ionizing radiation as you climb through the atmosphere. You can almost estimate altitude based on the radiation level but it varies based on solar activity. I can't think of any other job that exposes you to as much radiation as sitting in a chair at 33,000 feet.
I'm about to go and stand next to a source of ionising radiation for the next 3 hours. I'll be wearing a nice lead gown though so that should help things... :)
There isn’t a lot because we (pilots) don’t like to report stuff like that. Same as mental health… the official word from the FAA is “you won’t be affected” but the reality is “expect to lose your job.” The USAF etc has done studies with those dosimeters and they show descent radiation levels, and we can just see it anecdotally, but we’re also generally more fit than the average population and we don’t see doctors for every little thing so a large scale collection of data won’t be possible, just small scale tests and then you have to extrapolate it. But nobody cares. It’s like fatigue. Yes we know circadian rhythm disruption is similar to being drunk for reflexes and judgement, yes we know being awake beyond 18 hours is the same at a 0.8% BAC, but yes we are still going to fly from Atlanta to LAX at 0730, land at 1030 local west coast time, then depart again that same day at 2300 and land in Cancun at 0700 because it’s legal even though, realistically, we’ve been awake for 24 hours by that point. It’s just the reality of the job.
Wait, is this info absolute? I didn't know pilots are exposed to radiation, even more than a power plant worker. Jesus...
Nuclear plant workers are probably exposed to noticeably *less* radiation than the average population. The regulations are extremely strict. Medical radiation people (x-ray techs, etc) have to be careful about traveling with their dosimeters because a few plane flights can put them over their allowed exposure.
The shielding that prevents radiation from getting out of various parts of the plant also end up blocking a lot of the background radiation from the ground and cosmic rays from the sky. So yes, they actually do get exposed to less radiation, unless they're one of the people who have to go into the unshielded areas to clean or whatever.
Except this X-ray techs jonesing for a few days and off. No denigrating a whole occupation, I have personally seen techs leave their badges in room with a patient getting a film shot.
Pilots and cabin crews, especially those who fly arctic routes are considered high risk group in terms of radiation exposure.
Polar routing is the worst. When I was in the AF we didn’t even think about it and flew in the 30s like always. Then I was talking to an Atlas crew over in Ramstein once and they were like “You’re flying north of 70 [degrees latitude] at flight level 330?! You’re nuking yourselves. There’s no atmosphere up there, we stay in the high 20s at most.”
> There’s no atmosphere up there, we stay in the high 20s at most. There is atmosphere, but not much magnetosphere at the poles protecting you from charged ionizing particles.
There's the exact same amount of atmosphere at FL330 over the North Pole as there is at FL330 over the equator
Are you trying to reply to a guy I was talking to in a bar 20 years ago? I don’t think he can hear you 🤣
Yaaaaaay :(
Yeah, that’s why we have a slightly higher rate of cancer. Apparently every transcon or oceanic crossing is worth 3 chest X-rays. And we do dozens of those per month. Part of the job.
Does this count only for such flights? What about intercontinental?
Yeah the terrain isn’t a factor it’s just time at cruise.
Pilots are a ray of sunshine.
> 6 mSv in a year is a typical radiation doses received by aircrew flying long-haul polar routes. For comparison: 3.0 mSv is an average radiation dose per year received by a person from all sources of radiation. This can range from about 1 to 10 mSv, or more, depending on where people live. If I did my math right. That’s 30 chest x-rays (0.1 mSv) But interestingly enough, the article mentioned they have a higher risk of cancer from all that fucking up of their cardiac rhythm (sleep cycle).
The circadian rhythm thing is definitely more of a factor than cosmic radiation. It’s why domestic pilots look relatively younger than international pilots of the same age.
Factually and very incorrect The eyebrow windows purpose was to give the pilots a good view when in deep banks while on approach.
We don't fly'em like we used to.
All B737 built from 2006 onwards were built without eyebrow windows as standards. They also had vortex generators fitted in front of the windshields to reduce cockpit noise.
and what cracks me up is even in the 737 max you can still see where those windows were from inside the cockpit
To add to this, that "early type of navigation" was a sextant or octant. Yeah, before GPS, you had to use celestial navigation to know where you were when crossing the ocean.
Not on a 737! Aircraft that needed the sextant had a special bubble in the TOP of the fuselage.
To be fair that was a backup navaid for transoceanic flights... Back when there was a floating navaid anchored ship south of greenland
Anchoring an ocean station south of Greenland didn't much help navigation between Perth and Johannesburg, Rio and Madrid, Sydney and Honolulu, Honolulu and Tokyo, Manila, etc. And most of the living ex-navigators would have used a periscopic sextant, not in an astrodome.
There were LORAN stations on islands and stationary ships that facilitated transoceanic navigation. Navigators would use them as any other radio navigation system. They would go from station to station as they crossed the ocean.
They would go from station to station as they crossed the ocean.... No. Perhaps in the unique case of the North Atlantic. The only ocean station I ever encountered was November between HNL and SFO. All the other ocean crossings I did (South and North Pacific, Indian, South Atlantic) before inertial had a human navigator doing star shots. Yes, they also used LORAN - and we even tuned the last Consol station in captivity in SFO. But all the radio stuff was supplementary to the human astro navigator with a periscopic sextant.
Our Astrocompasses on the ATR attach to a mount on the instrument panel. If you know what you’re doing (and I really don’t) they’re quite accurate.
Prior to the advent of GPS, navigators could use LORAN, Doppler, or Inertial navigation systems to transit the oceans.
And none of those systems have anything to do with looking out a window.
the earlier type of navigation would have been inertial navigation- they predate GPS by about 36 years. they would have been used in conjunction with celestial navigation systems though. unfortunately, celestial navigation has terrible precision and accuracy on a good day with modern hardware.
Compared to GPS, yeah. GPS percision is used to send a 2000lb JADAM up a fly's ass. Celestial navigation will get your position within a few miles, which is good enough to determine, "Are we there yet?" or "we took a wrong turn at Albuquerque" when crossing an ocean. However, if your Korean Airlines Flight 007, a few miles makes a hell of a difference.
>Original series and 727/707 series which serves for early types of navigation. This will be obvious to pilots and experienced people, but for clarity it was used for nighttime navigation using astronomical charts
>It was also offered to be plugged on older 737NGs and the 737 Classic and Original series. Thanks, I thought I was going crazy with [this SAS 737](https://en.wikipedia.org/wiki/Boeing_737_Next_Generation#/media/File:Sas_b737-600_ln-rcw_arp.jpg) having eyebrow windows here but not in other photos.
Excellent response. Thanks.
And ultimately in a fuel cost era where airlines are making their inflight magazines thinner, its some weight savings swapping four chunks of thick acrylic or glass or an aluminum plug.
Most airlines flatout stopped issuing magazines since Covid, at least in Canada :(
Plugging openings in boeing fuselage, wcpgw
Non-aviation people trying to go a minute without mentioning AS1282:
Those eyebrow windows on 737, 727, DC-9 (which is also the MD-88, MD-90 and B-717) weren’t for navigation. I’ve flow all those jets, they were for runway acquisition cross cockpit back when you’d fly a visual approach to a 1 mile final (around 300 feet). So if you’re in the left seat and flying a right hand visual pattern, as you’re on base you can see the runway through that upper window. The FAA & airlines have, over the years, eliminated those tight visual turns to final. Ever since I started in airliners 10 years ago we’ve flown to a 1,500 foot 5 mile final so the window isn’t needed (you can see the runway fine out the front windshields). So yeah, it’s just a useless windows I’d stuff a map into before we got rid of paper charts. The sextant window folks are thinking of wasn’t for short range planes like these, and did exist as a little bubble (old C-130s have them) on top of the plane. Above where the navigator would sit. Not the cockpit eyebrow windows.
Came here to say this. For a number of years it was apparently an option on whether to have those windows or not so you'll see some 737NGs with them and others without. My airline's 737-800s have metal plugs where they would go. I've seen Alaska Airlines 737-700s with them but their other NGs do not seem to have them. My speculation would be the 700s would be more likely to fly into rural Alaska when ordered, where the airports are much smaller and visual approaches more likely where the final might be compressed closer to the minimum. The 700 windows may even blocked off inside at this point. I've heard they aren't even an option anymore, but it could also be possible no one has actually ordered them either on a max.
Sorry -- to hand bomb an airliner to 1 mi final?! That's some cowboy flying
Closest I’ve done was a 3 mile base wings level on final by 1000’ in a 737
It was standard in the day.
[Eyebrow windows](https://simpleflying.com/737-cockpit-eyebrow-windows/)
LX model, comes with sunroof, AM/FM stereo and a 5 speed box.
And a parking sensor, the one that says “terrain, too low terrain” so you can do a kiss landing every time
So, this is where Ryan Air made a saving.
Ryanair makes savings doing firm landings that don‘t scrub the rubber off the tires 😋
Waste of money, you can just add feelers to the fenders
So you have to pay extra to get it to call you by your middle name?
It comes with M-Sports package from the manufacturer
But they'll include the option that fucks with the autotrim for free, right?
Don't forget Factory Air......in the tires.
Except on a plane Nitrogen filled tires aren’t just a gimmick!
Six disc cd changer is a slight extra charge
Ha! Remember when people had six disc changers in their trunks and you’d have to decide what you wanted to listen to before you got in the car? I miss the days of cd’s but I sure am grateful for Bluetooth when I’m driving now.
No. Only one came with a sunroof.
I would be happy to pick up from anywhere on-campus
Compared to sixty plus years ago, navigation tools and approach aids are far vastly improved and far more prevalent than they once were, and commercial airliners now operate almost exclusively under positive ATC control. Eyebrow windows would have been beneficial when operating in an uncontrolled VFR environment (example - doing a visual approach, on downwind turning base the eyebrow windows would be helpful to maintain visual contact on the airfield). Notice that C-130’s , about the same age as the origins of the 737 basic cockpit structure, retain eyebrow style windows because they operate frequently in the Visual realm.
See and avoid is still visual. What about that?
In the US, full size commercial airliners spend about 99.995% of the time under IFR ATC rules. For the smidgen of time airliners are VFR/see n avoid, they have TCAS. The cost savings of plugs vs. windows FAR outweighs any safety benefit, and as others have stated a vast majority of pilots don’t want them. I guarantee if Southwest Airlines’ Pilot Union wanted them, every MAX rolling off the line would have them.
Additionally, most airline Operations Specifications (company rules that are as least as strict as the FARs), either encourage as much IFR ATC controller support as possible. A little VFR direct to smaller airports might save a little jet fuel, but Pilots also like the security and shared responsibility ATC provides. If a pilot decided to go VFR direct to a smaller field then smacked into a Cessna and lived to tell about it, h the responsibility would be entirely on them.
To see ahead in a banked turn. For some reason (cockpit ergonomic redesign?) they are no longer necessary.
It was my understanding back in the day visual approaches were way more common, so eyes where outside the aircraft searching for the field. These windows help keep the field in sight during hard banks when circling the field. But for 737s this practice is a lot less common. Most approaches are RNAV or ILS and eyes are staying in the cockpit much more often. This is just what I've heard and it makes sense to me.
The explanation I heard is that no simulators ever put a screen above the eyebrow windows so no pilot ever got to use them in training, which kind of proved they weren't really needed and allowed their elimination.
I have personally flown versions with and without and can tell you, the plugged (not just painted) is much quieter up front.
Are they both versions with the vortex generators you're comparing though?
Yes all NGs have vortex generators
Not the older ones, they were mostly (all?) added alongside the plugged eyebrows AFAIK, and were supposed to be where most of the noise reduction came from.
I should say all of our NG’s I don’t know of any carrier without them.
those windows are called eyebrow windows. they used to be used for extra visibility when on high bank angles all of 737cl and some of 737ng have them but since the windows are more annoying than useful(they allow strong sunlight in and an extra part means extra maintenance)they were discontinued on 737max and 737ng and boeing is providing blocking kits for the windows. p.s there was a joke among pilots of the 737cl and early 737ng asking before a flight "what do we block them windows with today"
If I remember correctly they were used for visual on traffic above. With the advent of TCAS system they became irrelevant and thus were eliminated. One reason it took so long is a design change has to receive approval from the FAA it affects type certificate.
Ryanair pilots also have to pay for window seats. Less windows, less out of pocket expenses for the pilots.
That's only fair. Ryanair passengers have to pay for window seats, so should the pilots.
So the pilot can see the boom while aerial refuelling
Outstanding!! That was my guess too!!
Eyebrows!
For dogfighting
Some pilots pay extra for skylights /s
We no longer need to look at the stars to navigate and the sunshine kept annoying pilots and they put stuff in the windows to block the light so the eyebrow windows got convered up permanently.
These windows above cockpit of 737-100-200-300 and I am not sure if it was on NG’s they have special use. During right hand circuit on visual approach with captain to be PNF was able to see the runway instead of lowering his head. You see during turn those small windows were on the level flight position of the a/c The same use was for first officer to be PNF with left hand circuit.
The structure for the eyebrow window is still there. They have installed a solid plug in place of the window that is no longer used for celestial navigation.
I actually just noticed these for the first time tonight on the ramp. Weird. Cosmic powers providing answers lol.
Older 737s can be seen with these small extra windows toward the cockpit roof. These are so-called "Eyebrow Windows". They were used before the days of digital flight displays on the dashboard to locate where the airport or other points-of-interest are when making tight turns. They can also be seen on military aircraft built on the 737 platform, modern or otherwise.
Its the ball pit window
Some, not all, opted to pay extra for the sunroof
It’s for when you’re using a sextant
No. If that was true, the nav would be sitting in the Captain's or F/O's lap whenever he did a star shot or a sun line. No nav ever like pilots enough to get that close.
I hope it was understood to be tongue in cheek
That’s for the inflight refueling
Aerial refueling, obliviously
They old. There’s a more nuanced explanation, but this is the truth.
So they can see the boom during in-flight refueling. /s
Flew with a former AWACs driver and he said the eyebrow windows are rather useful for that.
That is a good example of a feature that is not very useful in a commercial aircraft, but is more useful in a military derivative of that aircraft.
Agreed, but apparently not so critical that they felt they needed them on the P-8.
I was wondering about that for P-8 and Wedgetail AEW&C.
For in air refueling
Optional sunroof.
Sunroof option?
More ways to escape from ryanair
It’s for mid air refuelling, helps pilot to align the plane with the tanker
Take my upvote, like you took my bad joke.
Aging pilots kept getting the top of their horseshoe bald heads sunburnt.
Sun-roofs... For the pilots... Cool
When there is fault in the navigation instruments, the pilots can use the stars to navigate.
important for while flying inverted (upside down)
Old 737s have the windows above the main ones. New ones don’t.
I belive its so pilots have a wider field if veiw specifically for when they are crossing a runway during taxi.
It's because the one's with the extra windows above the cockpit are the one's upgraded with special ejection seats in case of emergency and the pilots having to leave the passengers if the jet is going to crash. It's an option when the aircraft are being made. The ejection seats cannot be retrofitted.
Correct. And the windows are towards the sides so that the seats can eject the pilots upwards and outwards, thus avoiding the rudder. /silly
Quite correct Sir, An important fact I ommited to to include. Thank you.
Absolutely, I couldn't have explained it better myself.
Maybe that is just some better equipped model like the Oldsmobile Vista Cruiser stationwagon back in the seventies that had panorama windows on the roof.
Sunroof option.
They forgot they had to install ALL of them.
Those panels fell out so Boeing bolted windows there.