Just out of curiosity - Airplane Guys

Grimly

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The caption mentions 70 years on, so this pic was taken 2014. They're probably all gone, now.

paratroops market garden 2014.jpg
 

jetmechmarty

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Even the early JT-8D's could be built oil tight. I once took a B727 (3 engines) on a 2 week "road trip." I threw 4 cases of MobileJet 254 in the fwd hold. 2 weeks wound up being 3. I ended with 3 cases and a few qts still in there. An outlier... but they could hold their oil when properly looked after.
Big company. Lots of jets. No such luck. At least not consistently.
 

40north

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Thanks fellas. The YB49 story evidently enhanced the reality ;) ! But as I remember they said the engines were of an oily disposition. Docs can be deceiving. As we all know, there are seals, and there are seals...

Noting that your experience is professional and commercial/military and begins after the early stuff...if I were doing "mod 1 mk 1" I'd not bother with proper seals, maybe labyrinth, and I am recalling that turbopumps in titan (Atlas? Ah fergit) were total loss (!) (1% or so Si oil mixed in fuel, iirc) Turbopumps being mere variation...I have the impression that this was once the case, and may still be in the very small jets that get used on one way trips, so to say. The weapon pushser motors as in zone 404, or whatever.

When I made a study of pulsejet reed design, and these are early jets of course, I discovered that the US forensic examination of V1 motor led to experiments with reed life, and quite reasonable and expected fact that the reed life was majorly extended by running oil through the reed/seat pairs. They smoked very nicely... and I think it's pretty.

I miss the simple stuff.
 

Jan_P

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? ?
How is the oil temperature regulated on a Jet engine ?
I know from excavators that Hydraulic fluid don't flow good at low temperatures Mostly problematic at start up
Harsh winter climate.
And the engine main bearings Is there not hot at times as a kerosene burner and cold other times
Say taking off from Africa somewhere Nairobi can be + 50 C at ground and then some time later - 50 C at altitude
Must be a reservoir oil many hundred liters hydraulic and large bearing oil tanks.also
Taking off Helsinki in winter can be - 30 C at ground
 

Jim

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How is the oil temperature regulated on a Jet engine ?
Just about all that I worked on use a fuel/oil heat exchanger. It's a "twofer" affair. Oil passes through the main body of it and fuel passes through tubes arranged inside the body... so we get the twofer....
The hot oil heats the incoming fuel. That's to melt any ice crystals that may form in the fuel at the -60° high altitude environment... which would restrict the fuel filter.
This in turn, cools the oil going back to the oil tank. Two for one.

1699638581586.png
 

Vincenthdfan

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Just about all that I worked on use a fuel/oil heat exchanger. It's a "twofer" affair. Oil passes through the main body of it and fuel passes through tubes arranged inside the body... so we get the twofer....
The hot oil heats the incoming fuel. That's to melt any ice crystals that may form in the fuel at the -60° high altitude environment... which would restrict the fuel filter.
This in turn, cools the oil going back to the oil tank. Two for one.

View attachment 254941
Oh man did those words give me some serious flashbacks!

The ole "FO-HE" as we used to call them on F-15's. We pulled and changed those things like our underwear....daily!

What a friggin messy pain in the butt those things were. There were two of them, side by side way up between the engines.

They contained a "thermal element" inside them that controlled the rate of fuel flow return from engine feed to the wings, acting as a thermostat if you will.

They failed with alarming regularity and resulted in wing fuel imbalances very, very often. After extensive engine run troubleshooting to verify a failed element, a defuel was required, then removal of accessory drive oil and hydraulic lines, engine oil lines, etc....all attached to heat exchanger that required cooling from the fuel.

Of course, the whole time you're pulling said lines, they're draining on your head, down your face, your body, etc....

Then when you finally pull the heat exchanger, the residual JP-8 (JP-4 back in the day) would pour out and piss all down your body too.

Ah yes, great memories. 😆
 

Jan_P

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Well nothing to do with flying but a story from the work experience Still circulating + 20 years later
Excavator company had a testbench for Hydraulic valves for the joy stick and some experiments was done to get better feel and less vibration
If I recall right it was 65 bar.pressure
The man Göran doing the tests was a bit afraid for the boss as were many others it was a tough no nonsense old school boss.

So before going further he got the boss on site to check it out giving approval Boss there in suit White shirt and Tie
Not saying it was the latest Italian creazione but a suit.
Göran being nervous should start the test .Hitting the button on the test bench ..And so he did .But the wrong one
It was the the one one step to the right with nothing connected on the outlet .And there should have been av valve preventing outlet if nothing connected .Not so

Boss man showered in small droplets Hydraulic fluid top down More oil in the hair than Elvis att Las Vegas concerts.
Göran got stop on the pump .but it was done ..I was at the compartment beside with a glass wall in between could see the Indoors Oil rain

How do you get home doing a change bathed in oil .You cant use your car and no Taxi will haul you

Surprisingly the boss took it well probably he did not want to get it out that he had defect safety valves

There was some suspicions that it was a devious plan .But it was dangerous so not many believed so
 

40north

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I have heard from a cat that was engineering tech at big wind tunnel test...2 am, footstep, the cat's slimed underneath the tunnel floor in hydraulic oil... "footsteps overhead" --- who's there? "It is I, Werner..."
And the pair, blue collar and nazi boffin, worked as one team slimed in oil to prepare for the test in the morning... So with these ears from the tech fella... army contract...meet lotsa people... long time ago. ;)
 

Jan_P

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I have heard from a cat that was engineering tech at big wind tunnel test...2 am, footstep, the cat's slimed underneath the tunnel floor in hydraulic oil... "footsteps overhead" --- who's there? "It is I, Werner..."
And the pair, blue collar and nazi boffin, worked as one team slimed in oil to prepare for the test in the morning... So with these ears from the tech fella... army contract...meet lotsa people... long time ago. ;)

Not to keep on straying off topic after a couple of shots to the Friday night chicken
Not sure if Wernher was a Nazi .. He may have been or not
When politics go bad there is not much room for alternatives

My Grandfather lived in Finland and there was a civil war red and white
cones the group asking are you with the reds or whites.
He got it right got a Mauser rifle and was recruited . Instead of getting shot at the spot
First possibility at night he left ..leaving the S**t He did not want to fight.

Being street smart the same way as in the dark alley Getting it wrong and getting into trouble
Feeling the environment and adapting

Wernher was dealing with murderers .. If they come asking there is only one answer
If one wants to survive as Bobby Womack puts it Across 110 th street

Not having opinions on politics or Wernher Just saying that if Gestapo comes or SS there was only one answer as for my Grandfather Those who rules and those who obeys.

In a top down fascist regime the man on the bottom cannot speak the truth . Look at other tyrannies today
Speaking up you can only provoke a reaction against yourself . >You cannot change anything or improve anything In Wernher's case a one way ticket to the Eastern front perhaps

Is that a spinless coward ...not refusing develop weapons for a crook regime Well that is another discussion off topic I go get another shot Vodka instead
Subject Doers those who spit in their hands and makes it happen and Talkers calling another press conference
 

Jim

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The B-21 Raider made it's maiden flight today. Considering the B-2 made it's maiden flight 35 yrs ago... and the B-1 almost 50 yrs ago... it's about time for an upgrade, huh? The B-21 is planned as a replacement for both the B-1 and B-2


 

40north

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Not to keep on straying off topic after a couple of shots to the Friday night chicken
Not sure if Wernher was a Nazi .. He may have been or not
When politics go bad there is not much room for alternatives

My Grandfather lived in Finland and there was a civil war red and white
cones the group asking are you with the reds or whites.
He got it right got a Mauser rifle and was recruited . Instead of getting shot at the spot
First possibility at night he left ..leaving the S**t He did not want to fight.

Being street smart the same way as in the dark alley Getting it wrong and getting into trouble
Feeling the environment and adapting

Wernher was dealing with murderers .. If they come asking there is only one answer
If one wants to survive as Bobby Womack puts it Across 110 th street

Not having opinions on politics or Wernher Just saying that if Gestapo comes or SS there was only one answer as for my Grandfather Those who rules and those who obeys.

In a top down fascist regime the man on the bottom cannot speak the truth . Look at other tyrannies today
Speaking up you can only provoke a reaction against yourself . >You cannot change anything or improve anything In Wernher's case a one way ticket to the Eastern front perhaps

Is that a spinless coward ...not refusing develop weapons for a crook regime Well that is another discussion off topic I go get another shot Vodka instead
Subject Doers those who spit in their hands and makes it happen and Talkers calling another press conference
iirc he was NSDAP member and officer in the SS. But of course, there is always a choice, not very nice ones, but choice. The Finns had some rough times. Geography! Alas.
 
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