- Aircraft Year
- 1974
- Aircraft Type
- 112 Hot Shot
- Reg Number
- N1144J
- Serial Number
- 186
What altitude do you normally fly at? The 114HS already makes more power than the Super above 7K ft.
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112 Hot Shot
- Thread starter carllee
- Start date
What altitude do you normally fly at? The 114HS already makes more power than the Super above 7K ft.
Medevac
New member
Brisbane, Queensland
- Aircraft Year
- 1977
- Aircraft Type
- 114
- Reg Number
- VH-RNS
- Serial Number
- 14312
I haven't flown much in mine but with OATs of 35C, the density altitude here is a killer. I was at 3000' and max throttle and is was really anaemic. It seems boosting the engine is so much easier than the engine swap and if one is putting a turbo on anyway, would it be that much of a step?
- Aircraft Year
- 1974
- Aircraft Type
- 112 Hot Shot
- Reg Number
- N1144J
- Serial Number
- 186
Sorry, I'm not understanding your question. What do you think a turbonormalizer does? If you were experiencing anaemic performance because the DA was 3K ft wouldn't you prefer to have standard sea level performance? "Normalized to sea level DA"
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Medevac
New member
Brisbane, Queensland
- Aircraft Year
- 1977
- Aircraft Type
- 114
- Reg Number
- VH-RNS
- Serial Number
- 14312
Doesn't the normaliser normalise it to sea level? But if your sea level is 35* OAT then your DA is already 2400' (20*C difference x 120'/*C) even if at sea level. In order to actually get sea level performance, you're going to need to turbocharge it and have a higher intake pressure and intercool it.
- Aircraft Year
- 1974
- Aircraft Type
- 112 Hot Shot
- Reg Number
- N1144J
- Serial Number
- 186
The engine has no idea where it is, how hot it is, or how high up it is. It's just a dumb machine that pumps air. If it gets 28.5" of manifold preassure it can produce 260hp. The turbonormalizer can give the engine 28.5"+ of manifold pressure at any temperature, or altitude up to 18Kft. Above 18Kft the manifold preassure drops at the same rate as a normally aspirated engine's drops from sea level. A naturally aspirated engine makes Rated HP at 28.5" of manifold pressure (basically standard sea level pressure, 70 degrees, 29.92" of mercury). The 28.5 number allows for some resistance of airflow into the engine, filter, plumbing, etc. There's 1/2 as much air pressure at 18K ft (that's why the airspace restrictions, rating restrictions, etc - the magic number 18K) as there is at sea level so a naturally aspirated engine can only produce 1/2 as much HP as it's Rated for at 18K ft. That equates to roughly a 3% loss of Rated HP for every 1000ft a naturally aspirated aircraft climbs. Any change in DA due to temp, of course, has the same effect - so if you're at sea level elevation, but the DA is 3000ft a naturally aspirated aircraft will make around 10% less HP than it's Rated for. The math is simple and can be applied to any naturally aspirated engine 3% loss per 1000ft, 1/2 Rated HP at 18,000ft.
Planecents
New member
Cameron, TX
- Aircraft Year
- 1976
- Aircraft Type
- 114 Hot Shot
- Reg Number
- N4771W
- Serial Number
- 101
The 112TC boost is 42” and it goes from 200 to 210 HP. The 114 NA and normalized is 260 HP. The NA starts dropping off with your DA before even leaving the runway. The HS takes 260 HP up to a high altitude. Sorry, I don’t have the POH in front of me, but Carl can answer what altitude it starts dropping off. If you want a turbo charged 114 now, the only option is a 114TC. Too small of a sample size right now to make a non factory TC STC development affordable.
(looks like he already did)
(looks like he already did)
Last edited:
Medevac
New member
Brisbane, Queensland
- Aircraft Year
- 1977
- Aircraft Type
- 114
- Reg Number
- VH-RNS
- Serial Number
- 14312
I think we're all on the same page here Thanks for the explanations guys, appreciate the responses.
What I was saying is that the engine will make 28.5" at any temp but because of the high temps here, the DA incurs a 10% penalty immediately. Then again, that's only in summer so on cooler days here, it's probably about right.
I'm still down for a 114HS.
Thanks for the explanations guys, appreciate the responses.What I was saying is that the engine will make 28.5" at any temp but because of the high temps here, the DA incurs a 10% penalty immediately. Then again, that's only in summer so on cooler days here, it's probably about right.
I'm still down for a 114HS.
San Diego, CA
- Aircraft Year
- 1974
- Aircraft Type
- 112/A
- Reg Number
- N144TP
- Serial Number
- 144
"(basically standard sea level pressure, 70 degrees, 29.92" of mercury)"
Carl,
Is 70 degrees correct? My understanding in aviation everything is rated to ISO conditions of 15'C (or for us metric challenged Americans 59'F), standard sea level pressure and 60% relative humidity. I thought these numbers are in the AMSE Power Test Code. The only other rating I'm aware of is NEMA (National Electric Manufactures Assc.) which is 80'F @ 1000 ft elevation (std conditions apply) is sometimes used for internal combustion powered generator sets, but is really reserved for motors and power generation equipment...
Regards - Clark
Carl,
Is 70 degrees correct? My understanding in aviation everything is rated to ISO conditions of 15'C (or for us metric challenged Americans 59'F), standard sea level pressure and 60% relative humidity. I thought these numbers are in the AMSE Power Test Code. The only other rating I'm aware of is NEMA (National Electric Manufactures Assc.) which is 80'F @ 1000 ft elevation (std conditions apply) is sometimes used for internal combustion powered generator sets, but is really reserved for motors and power generation equipment...
Regards - Clark