Unanswered Questions
25 questions with no upvoted or accepted answers
3
votes
0
answers
380
views
How does the maintenance cost of turboprops compare to turbofans?
I was initially under the impression that the added complexity of gearing in a turboprop would lead to more maintenance. Then I found out geared turbofans are becoming fairly common so there should be ...
- 611
3
votes
0
answers
81
views
What are the differences between a compressor wash on wing vs on test bed
I work in an aircraft engine overhaul facility and I’m trying to understand the process of compressor washing engines on Wing compared to washing them in a test bed. What process steps are different ...
- 28.8k
3
votes
1
answer
368
views
What is the aerodynamic influence of prop spacing and placement in multi-prop engine setups
I saw this question Is there a rule of thumb for spacing between jet engines?, which referred to How do you choose engine placement for under wings engines?, but I was wondering how the engine spacing ...
- 21
2
votes
0
answers
204
views
How does the ETOTS system work on the A380, and what does it limit?
To my knowledge, all A380s with Trent 900s have thrust limited to 78% N1 until 35 knots speed (not sure if ground or airspeed). Would appreciate any expert knowledge on anything else that is limited ...
- 55
2
votes
0
answers
230
views
Why B737 CFM56 engine sounds like heavy wind sound at Throttling up?
14:14 ~ 14:21 : Throttle Up (with heavy wind sound
14:22 ~ 14:23 : Engine reached certain %, and no heavy wind sound
14:23 ~ : Throttle Up (with heavy wind sound)
I always wonder why only B737NG with ...
- 22.7k
2
votes
0
answers
1k
views
What happens if you put too much oil into a reciprocating engine wet sump?
Apparently putting too much oil into your airplane engine is really bad and can be expensive but why? Will the excess oil go out via the oil breather,... ? Thank you
- 937
2
votes
0
answers
940
views
How hot is the outer casing of a turbofan engine?
I am able to find temperatures inside different components of turbofan engines, but I can't seem to find what would be the temperature of the external casing/shell of the engine. For example, ...
- 41
2
votes
0
answers
329
views
Are subsonic nozzle fully expanded?
this is about converging subsonic nozzles.
Are they fully expanded? meaning exit pressure=ambient pressure?
What about diverging subsonic nozzle?
Are they fully expanded? what would happen if the ...
- 411
1
vote
0
answers
117
views
C130J - AE2100D3 Engine - Do dirty landings affect the development of burnthrough in NGVs?
Burnthrough fundings in AE2100D3 engine that experienced exessive amount of dirt landings
- 97.4k
1
vote
0
answers
281
views
Engine Performance Data for GE F414-400
I am currently in Capstone for ASE, and for our course we have been tasked with reverse engineering the X-59 QueSST created by NASA and Lockheed Martin. I am the propulsion lead for our team and I ...
- 11
1
vote
0
answers
204
views
Why are hydraulic pumps mounted on engines 2 and 3 in BAe 146?
The BAe 146 has 4 engines:
engine no. 1 and 4 generate electricity
engine no. 2 and 3 generate hydraulic pressure
Why was this setup chosen?
- 60.4k
1
vote
0
answers
156
views
Would the dle 55ra engine be enough to power my paramotor(ducted fan)?
I plan on using the dle 55ra engine to produce 5hp at 8,500 rpm. I am using it in a paramotor, and to save space I am considering using a ducted propeller similar to the Fulcrum power pod. The duct ...
- 137
1
vote
0
answers
531
views
What is the specific fuel consumption and cruise thrust of PW1521G engines?
I'm looking for the specific fuel consumption (SFC) and thrust related to PW1521G in cruise regime, as well as the associated assumptions for these ratings. I can't find them online.
- 2,969
1
vote
0
answers
388
views
Do modern aircraft still have PCMCIA?
Do modern aircraft still have PCMCIA for engine monitoring?
- 519
1
vote
0
answers
135
views
What Microcontroller(s) is/are used inside the ECU of a CF6-80C2 engine?
The question came up at work today and no one knew the answer. Did some digging online and could not find anything definitive.
- 11