Unanswered Questions
43 questions with no upvoted or accepted answers
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Why is the F-104 Starfighter’s afterburner thrust not greatly impacted by altitude?
Here is a page from the F-104 flight manual. It shows the flight envelope for the F-104 Starfighter with the powerful J79-GE-19 turbojet engine:
I have a question regarding the shape of the ...
- 28.8k
4
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0
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856
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RR Ultrafan: Why the dramatic change of fan blade design?
The Rolls Royce Ultrafan prototype has been in development for a few years and has usually been seen in the media with very distinctive curved leading edge design as such:
However, this week (...
- 32.9k
3
votes
0
answers
140
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What legacy turbojet would have detailed documentation and drawings available for free or cheap?
I am fascinated by the technology of jet engines. As a hobby, I might like to create a detailed animated 3D model of one (and publish it with a Creative Commons license). Obviously I am not going to ...
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3
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What is the highest operational ceiling for a nuclear scramjet?
A similar question is:
What is the highest operational ceiling for an air-breathing jet engine?
The answers point to scramjets. Cited reports focus on combustion kinetics.
The Wikipedia Scramjet page:
...
- 51
3
votes
0
answers
207
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What is the speed of gas in the core of a jet engine?
Coming from a slightly related question, I want to know what is the speed of the gas in the core of a jet engine, after combustion but before the first turbine stage.
I'll just pick a random example: ...
- 18.1k
3
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0
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105
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Why would changes in jet-engine power settings not result in changes in engine loudness?
My casual AAR reading has dredged up another counterintuitive detail of aircraft behaviour, this time regarding the relationship between engine power and engine loudness:
1.16.7.3 Sound Similar to ...
- 28.8k
3
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0
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1k
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Can the assumed temperature be lower than the flat rated temperature?
I was playing with reduced takeoff thrust in a Boeing 737-800 simulator yesterday and was surprised that I could enter assumed temperatures below the flat rated temperature of the engines. The ...
CommunityBot
- 1
2
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0
answers
292
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NASA's and Boeing truss-braced wing fuel savings breakdown
According to its Administrator Bill Nelson, NASA is working on a project with Boeing that will reduce single-isle aircraft fuel consumption by 30%. He described it as a higher and thinner wing and ...
- 425
2
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0
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277
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Why do white marks on the spinners in front of engines have different patterns? Not Yellow? Omitted for some models?
In aeroailas' answer I understand that the cones in front of the props/fans are called spinners.
In Farhan's answer I understand that the ehite marks painted onto the spinners act less as scarecrows ...
2
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0
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298
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What are these holes on the intake of Progress D-18T which are mounted on AN-225?
I was seeing a Progress D-18T of AN-225 and saw these holes on the intake of them. What are they for?
- 3,359
2
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249
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Can anyone help identify this turbine blade?
At the local army/navy surplus store and found this in a "junk" box. Got it for $1. Would live to know what airframe this came off of. Im new to this so compressor blade? Compressor turbine?
...
- 21
2
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0
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321
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What is that to and fro moving thing?
This video by AgentJayZ is the maintenance and repair of AI-25 turbofan. What is that thing moving due to applying certain pressure to that pipe? Can anyone describe its purpose and how it works?
- 1,577
2
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0
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263
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How are Fan pressure of and Static pressure in the turbofan engine related?
If the fan air is ducted to the rear, the total fan pressure must be higher than the static gas pressure in the primary engine's exhaust, or air will not flow. By the same token, the static fan ...
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2
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6k
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What is the fan pressure ratio in a turbofan?
What is it and how does it affect efficiency and thrust?
2
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0
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290
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Why does the LEAP 1A HPT run at such a high RPM?
I've watched the N2 on the LEAP sit at 100% at cruise and fluctuate as high as 101%. Why does the HPT run at such a high RPM?
- 72.3k