First S-70i Helicopter Fully Assembled At Sikorsky Facility In Poland
By HIIRS I suspect you mean the Hover (Improved) Infrared Suppressers. If so, this is not the reason for the performance difference.
As noted by others on this thread, the Baseline S-70i has the old style metal blade (titanium spar, fibreglass skin with honeycomb core) as fitted on the ‘Lima’ and it does have T700-GE701D engines as installed in the ‘Mike’ - although with 701C ‘Lima’ fuel controls (Not FADEC), so an improvement over the ‘Lima’, but not as good as the ‘Mike’.
In simple terms, think of the S-70i as a UH-60L with a digital cockpit and improved T700-GE-701D engines, but without the ‘Mike’ FADEC control system.
The ‘Mike’ has wide chord composite blades (which provide greater lift) and T700-GE-701D engines with FADEC controls, which provides even more power and therefore more lift, so in essence it is these two upgrades that account for the main difference in performance between the ‘Mike’ and the Baseline S-70i.
As noted by others on this thread, the Baseline S-70i has the old style metal blade (titanium spar, fibreglass skin with honeycomb core) as fitted on the ‘Lima’ and it does have T700-GE701D engines as installed in the ‘Mike’ - although with 701C ‘Lima’ fuel controls (Not FADEC), so an improvement over the ‘Lima’, but not as good as the ‘Mike’.
In simple terms, think of the S-70i as a UH-60L with a digital cockpit and improved T700-GE-701D engines, but without the ‘Mike’ FADEC control system.
The ‘Mike’ has wide chord composite blades (which provide greater lift) and T700-GE-701D engines with FADEC controls, which provides even more power and therefore more lift, so in essence it is these two upgrades that account for the main difference in performance between the ‘Mike’ and the Baseline S-70i.
John Dixson is correct.
The S-70i has GE 701D Engines with 701 C engine controls. It now has the composite blades with titanium spars as baseline. This used to be available as the EPP option but is now standard.
Heli 1
The S-70i is approximately 1000lbs lighter than the UH-60M.
The S-70i has GE 701D Engines with 701 C engine controls. It now has the composite blades with titanium spars as baseline. This used to be available as the EPP option but is now standard.
Heli 1
The S-70i is approximately 1000lbs lighter than the UH-60M.
S-70i
Industry Insider and Hilife,
In talking to some acquaintances, it seems as if this may a situation overcome by events.
( BTW, the comments re the HIIRS and basic weight are correct )
It now appears that the Ti-composite blades will not be delivered, which in turn allows the FADEC*. So, depending on how the customer specs out his/her 70i, it may well have a bit better performance than an M, simply due to being lighter, and not having the HIIRS engine back pressure related losses ( though relatively small ).
* So why does the basic 70i spec reflect a 701D with 701C controls? I couldn't find anyone this morning who had the specific answer here, but this is my educated guess: there had never been an engine/airframe test program done for the combination: Ti-composite blades and 701D FADEC engines. This is not a trivial subject.If interested, send a PM and I can provide a textbook example about the initial attempt to install Woodward HMU's on the Hawk.
Anyhow, after a second look at the 70i spec, I'd hardly use the pejorative " lower trim grade " to describe the aircraft. The other comment that I'd add is that the SA Test Pilot on station at PZL is highly impressed with the workmanship in their shops.
Thanks,
John Dixson
In talking to some acquaintances, it seems as if this may a situation overcome by events.
( BTW, the comments re the HIIRS and basic weight are correct )
It now appears that the Ti-composite blades will not be delivered, which in turn allows the FADEC*. So, depending on how the customer specs out his/her 70i, it may well have a bit better performance than an M, simply due to being lighter, and not having the HIIRS engine back pressure related losses ( though relatively small ).
* So why does the basic 70i spec reflect a 701D with 701C controls? I couldn't find anyone this morning who had the specific answer here, but this is my educated guess: there had never been an engine/airframe test program done for the combination: Ti-composite blades and 701D FADEC engines. This is not a trivial subject.If interested, send a PM and I can provide a textbook example about the initial attempt to install Woodward HMU's on the Hawk.
Anyhow, after a second look at the 70i spec, I'd hardly use the pejorative " lower trim grade " to describe the aircraft. The other comment that I'd add is that the SA Test Pilot on station at PZL is highly impressed with the workmanship in their shops.
Thanks,
John Dixson
