MILAVIA Forum - Military Aviation Discussion Forum

Author Topic: Boeing B-17 Motorization  (Read 4547 times)

Offline Phigla

  • Recruit
  • *
  • Posts: 5
Boeing B-17 Motorization
« on: April 06, 2020, 08:42:00 AM »
As told in my presentation, I’m living in China and as messenger, Facebook, Twitter, even Wikipedia, other online encyclopedies are blocked by the Chinese cyber authorities my information resources are really limited…

I have questions , maybe you know the replies or maybe you can orient me to someone or somewhere. 

As well I read:
The Boeing model 299 was powered by a R-1690 Hornet
The Y1B-17 by a R 1820-39 Cyclone. 
The Y1B-17A by a R 1820-51 with turbocharger GE type B-2
The B-17E by a R-1820-65 cyclone. 
The B-17F by a R 1820-97 cyclone with turbocharger GE typeB-2
The B-17G by a R 1820-97 cyclone with turbocharger GE type B-22

Would it be possible to know:

What are the difference between the R 1820-39, 1820-51, 1820-65, 1820-97? 

What the difference between the R-1690 hornet and 1820 cyclone? 

Difference between the turbocharger GE type B-2 and type B-22? 

The difference between the 1690 hornet supercharged, the 1820 supercharged and the 1820 turbocharger? 

What is a R-1820 G2

Really sorry for all these questions,  I really don't find any replies regarding my limited information resources. 

Thanks in advance

Offline Webmaster

  • MILAVIA Webmaster
  • Administrator
  • General of Flight
  • *******
  • Posts: 2842
  • Country: nl
Re: Boeing B-17 Motorization
« Reply #1 on: April 06, 2020, 10:17:14 PM »
As told in my presentation, I’m living in China and as messenger, Facebook, Twitter, even Wikipedia, other online encyclopedies are blocked by the Chinese cyber authorities my information resources are really limited…

see attachments for Wikipedia, I included some extras, so it may make some sense.

and maybe theses excellent (pre-Wikipedia era) sites will work for you:
http://www.enginehistory.org/
http://www.aviation-history.com/
just search them for the Wright R-1820.

I have questions , maybe you know the replies or maybe you can orient me to someone or somewhere.

As well I read:
The Boeing model 299 was powered by a R-1690 Hornet
The Y1B-17 by a R 1820-39 Cyclone.
The Y1B-17A by a R 1820-51 with turbocharger GE type B-2
The B-17E by a R-1820-65 cyclone.
The B-17F by a R 1820-97 cyclone with turbocharger GE typeB-2
The B-17G by a R 1820-97 cyclone with turbocharger GE type B-22

Would it be possible to know:

What are the difference between the R 1820-39, 1820-51, 1820-65, 1820-97?
They are the model numbers given by the US army, odd numbered (navy used even numbers), higher is later series model and configuration.
Sorry I don't know how they exactly align with the Wright versions/series E/F/F-50/G. I believe the 1820-97 is the G-2 model?

What the difference between the R-1690 hornet and 1820 cyclone?
P&W -vs- Wright
1690/1820 is the displacement (rounded cubic inches), the higher the more potential for power output.
P&W had more success with the R-1830 Twin Wasp (2x7=14 cylinder) than the 9 cylinder Hornet.

Difference between the turbocharger GE type B-2 and type B-22?

I can't believe I found  this: https://aviationshoppe.com/manuals/wwii_aircraft_superchargers/wwii_aircraft_turbosupercharger.html
it's from the actual manual:

"Same as Type B-2, with the following exceptions:
1. Bearing lubrication redesigned and turbine bucket wheel made of improved material which permits 24,000 rpm rated speed.
2. Has 1/2-inch flexible-rubber oil lines"

rotor speed went from 21300 rpm to 24000 rpm, weight flow increase from 110 to 120 Lb/Min at altitude 25,000 ft.

See https://aviationshoppe.com/manuals/wwii_aircraft_superchargers/wwii_aircraft_turbosupercharger.html?pageNumber=12

The difference between the 1690 hornet supercharged, the 1820 supercharged and the 1820 turbocharger?
1) different engine
2) I'm not sure about the specifics, but if I go with the definitions, a supercharger is still driven by the engine, so takes some power away. a turbo(super)charger has a turbine driven by exhaust gases. Not sure that actually applies in these cases though.

What is a R-1820 G2
Yeah, so that's the Wright model G with a certain blower ratio for the supercharger, designated G-2. So configured with the GE turbocharger, it is the same as R-1820-97 military designation?
I'm not sure, not an expert!!

anyway check out the sources.
« Last Edit: April 06, 2020, 10:29:12 PM by Webmaster »
  • Interests: Su-15, Su-27, Tu-22, Tornado, RNLAF
Niels Hillebrand
MILAVIA Webmaster

Offline Phigla

  • Recruit
  • *
  • Posts: 5
Re: Boeing B-17 Motorization
« Reply #2 on: April 07, 2020, 01:47:52 PM »
Dear Niels Hillebrand,

Thanks a lot for the information you sent to me.

Let me read it, maybe I will come back to you.

Greetings from China, have a nice day

Best regards

Philippe

Offline Phigla

  • Recruit
  • *
  • Posts: 5
Re: Boeing B-17 Motorization
« Reply #3 on: April 16, 2020, 10:10:49 AM »
The evolution of the Wright engine used by the B-17 can be found at
http://www.enginehistory.org/References/ModDesig/moddesig.shtml

Offline Phigla

  • Recruit
  • *
  • Posts: 5
Re: Boeing B-17 Motorization
« Reply #4 on: April 26, 2020, 04:55:55 AM »
Dear Fellows

I have another trivial question
For the prototype Model 299 it was 9 crews, for the B-17F and G it  was 10 cews
For the Y1B17 I read 6 crews
My question is"
what is the number of crew and function for the Model  299, Y1B17, Y1B19A, B-17-B, B-17C,

Thanks in advance

 



AVIATION TOP 100 - www.avitop.com click to vote for MILAVIA