AeroWeanie From United States, joined Dec 2004, 1511 posts, RR: 38 Reply 2, posted (2 months 2 weeks 3 days 10 hours ago) and read 1863 times:
The CH-47 is much larger than the CH-46. The CH-46 has a max GW of 24,300 lbs, while the CH-47D has a max GW of 50,000 lbs. The CH-47 has far more installed power and larger rotors too. About all they have in common is the general tandem rotor configuration.
In comparing them, what really struck me was how roomy the interior of a CH-47 felt after walking through the relatively cramped interior of the CH-46.
BHMBAGLOCK From United States, joined Jul 2005, 2671 posts, RR: 22 Reply 3, posted (2 months 2 weeks 3 days 9 hours ago) and read 1853 times:
Other than size, here are a few very notable differences:
CH-46(some models) have power blade folding for shipboard operations
CH-46 has tricycle landing gear vs quad for the CH-47
The CH-47 can land in water unmodified, installation of a dam is typically used if the ramp will be opened unless recovering or deploying a boat. The CH-46 requires inflatables to be able to land in water, ironic considering the 46 was primarily sold to naval customers and the 47 primarily to the Army. The sponsons on the CH-47 provide the stability required for this.
CH-47 has a much more advanced external carriage system for slung loads
Although both models were developed in parallel (a lot like 757/767) they have diverged a lot over time. The US Army has put much more money into modernizing the CH-47 and acquisitions are ongoing while the CH-46 is being phased out as the V-22 replaces it.
The size of the CH-47 also allows more versatility, i.e. more avionics room, room for weather radar, TFR, gunship mods, etc.
Dragon6172 From United States, joined Jul 2007, 464 posts, RR: 0 Reply 6, posted (2 months 2 weeks 1 day 5 hours ago) and read 1538 times:
Quoting UH60FtRucker (Reply 1): ..but really, who cares? The real men fly Black Hawks.
Ugh.. what a piece of junk. It was amazing to me how much of a pain in the ass the H-60s were that came to replace a Phrog squadron. Needed three of them to do what two Phrogs could do. Now, I share a hanger with a Navy H-60 unit and their birds are constantly needing repairs due to massive cracks where the transmissions mounts. Phrogs Phorever!!
Quoting BHMBAGLOCK (Reply 3): The CH-47 can land in water unmodified, installation of a dam is typically used if the ramp will be opened unless recovering or deploying a boat. The CH-46 requires inflatables to be able to land in water, ironic considering the 46 was primarily sold to naval customers and the 47 primarily to the Army. The sponsons on the CH-47 provide the stability required for this.
H-46 can land in water unmodified as well if you do not have the left gunners window open. Water landings, taxiing, and takeoffs used to be part of the flight training syllabus, but was removed due to the intense maintenance effort required post water landing.
The HEFS (helo emergency flotation system, the inflatable bags carried on the side) were there to keep the aircraft upright and afloat in the event of a controlled emergency water landing. For example, a transmission related emergency where you needed to land and shut down. They were labor intensive, added 300 lbs ( or one Marine) to the aircraft weight, and the velcro that held them closed constantly failed and allowed them to hang uninflated. By the time I got out they had become an item that was required at the commanders descretion. Typically only used when deployed on ship and carrying passengers.
Quoting BHMBAGLOCK (Reply 3): CH-46(some models) have power blade folding for shipboard operations
All CH-46s have power blade fold. It does not always work, but the system is installed. BV-107, and KV-107s do not typically have the power blade fold. Much smaller and lighter rotor heads installed.
UH60FtRucker From Tajikistan, joined Mar 2005, 2635 posts, RR: 71 Reply 7, posted (2 months 2 weeks 1 day 3 hours ago) and read 1508 times:
Quoting Dragon6172 (Reply 6):
Ugh.. what a piece of junk. It was amazing to me how much of a pain in the ass the H-60s were that came to replace a Phrog squadron. Needed three of them to do what two Phrogs could do. Now, I share a hanger with a Navy H-60 unit and their birds are constantly needing repairs due to massive cracks where the transmissions mounts. Phrogs Phorever!!
Well Dragon... sorry to lay the smack down.... but I clearly said BLACK HAWK. Yet you used the Sea Hawk for comparison!
And also, I said real men. Sea Hawks are flown by squids! So of course they don't know how to properly run a H-60 unit! ....They're squid!!! Â Â Â
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No but in all seriousness, the early transmission mount cracks in the SH-60s have been resolved. The newer models featured the improvements, and the B models were retrofitted with the improved mounts.
Currently, fleet wide, they have an OCRR of 89%. Army UH-60Ls have a OCRR of 93%. Obviously with the saltwater environment and the rougher landing conditions, SH-60s require more attention, not to mention spare parts are harder to come by when you're at sea.
The Marines - who don't have H-60s - currently have a 70% OCRR for their CH-46s.
And to be fair... the Hawk does have a black eye - the USAF Pave Hawk has an OCRR of 54%. Â (Hence the argument for a dire need for the new CSAR-X)
StudeDave From United States, joined Oct 2006, 179 posts, RR: 0 Reply 8, posted (2 months 2 weeks 23 hours ago) and read 1452 times:
I'll leave most of the comments directed at the NAVY by the door, because I know you kid around- just as do I from time to time. This, however, needs comment~
Quoting UH60FtRucker (Reply 7): No but in all seriousness, the early transmission mount cracks in the SH-60s have been resolved. The newer models featured the improvements, and the B models were retrofitted with the improved mounts.
We've talked about all this before. Be careful when throwing that "SH" around- the "MHs" are the problem children~ Sierras in particular...
The Bravos, Foxtrots and Hotels are fine. Always have been- thery only have one cabin door. Sure they cracked once in a while, but not in the places (or as bad, or as early in life) as the Sierras. In fact alot of the older Bravos/Foxtrots are still flying- 20+ years later, and despite having flown well past their 'airframe life'! It's the "new" Sierras that are (were) having problems. With two cabin doors, the heavier duty drive train, and heavy work (VERTEP) combined with a weak structure- it didn't add up. Now throw an old Phrog Pilot in the cockpit, and it only gets worse!!!
There is finally a fix out there, but it wasn't too pretty while Sikorsky worked it out.
Dragon6172 From United States, joined Jul 2007, 464 posts, RR: 0 Reply 9, posted (2 months 2 weeks 20 hours ago) and read 1396 times:
Quoting UH60FtRucker (Reply 7): Well Dragon... sorry to lay the smack down.... but I clearly said BLACK HAWK. Yet you used the Sea Hawk for comparison!
And also, I said real men. Sea Hawks are flown by squids! So of course they don't know how to properly run a H-60 unit! ....They're squid!!!
Allow me to clarify. My main comparison was to Blackhawks. They relieved a Phrog unit at Al Asad, and started flying three plane divisions to keep up with what two Phrogs were doing. Since 85 percent of the flying was general support, moving people and cargo from A to B, I find that lack of cargo space a serious hinderence. Whats the point of having a higher carrying capacity if you got no room to freakin put anything.
The second part I was indeed referring to Navy MH-60S. At any given time they have 2-3 aircraft undergoing repair for cracking. One aircraft has gone twice in two years.
Phrogs have their downfalls, but they are reliable and have been around long enough that we know where all the kinks are.
Curt22 From United States, joined Jul 2007, 282 posts, RR: 1 Reply 10, posted (2 months 2 weeks 16 hours ago) and read 1346 times:
Quoting UH60FtRucker (Reply 7): And to be fair... the Hawk does have a black eye - the USAF Pave Hawk has an OCRR of 54%. (Hence the argument for a dire need for the new CSAR-X)
Not sure what "OCRR" refers to...never heard that term before, but yes, the USAF HH-60's are getting to be some old horses, put away wet with airframe ages in service from 1981 through 1990's models, and many with more than 7,000 hrs...most of which flown at or near MGW all of their lives with all sorts of bumps and warts that add stress and drag to the airframe, something a "slick" 60 rarely sees.
I wonder how TF 160's MH-60L/K's are standing the test of time in a similar configuration to the HH-60G?
Quoting Dragon6172 (Reply 9): The second part I was indeed referring to Navy MH-60S. At any given time they have 2-3 aircraft undergoing repair for cracking. One aircraft has gone twice in two years
Wow new MH-60S's already showing airframe cracks? Sure, I've heard of several 308 beams crack and even some gearbox webbing from time to time but these were on the much older USAF HH-60G's spoken of above. Sure is a drag to see new acft having old acft problems.
You're joking, right? This has been on-going since I can't remember when. Most cracked about the time they got around 2000 hours or so on the airframes- some sooner, a few later. There's a fix, but doesn't happen overnight...
Curt22 From United States, joined Jul 2007, 282 posts, RR: 1 Reply 12, posted (2 months 1 week 4 days 1 hour ago) and read 1134 times:
Quoting Studedave (Reply 11): You're joking, right? This has been on-going since I can't remember when. Most cracked about the time they got around 2000 hours or so on the airframes- some sooner, a few later.
Nope, not joking...just not engaged on naval rotary wing issues, so surprised to see new acft having these problems. The first 308 beam (and beaded panel) cracks I saw were in the early 90's on acft that were about 10 yrs old (approx 3500 flt hrs). First gearbox webbing cracks came much later...I wonder what SAC did, or didn't do on the MH-60S's that they did on the previous UH/HH-60 airframes to see cracks so much sooner?
Studedave From United States, joined Oct 2006, 179 posts, RR: 0 Reply 13, posted (2 months 1 week 3 days 23 hours ago) and read 1117 times:
Quoting Curt22 (Reply 12): I wonder what SAC did, or didn't do on the MH-60S's that they did on the previous UH/HH-60 airframes to see cracks so much sooner?
See post number 8, and other threads where we've talked about this. Number 8 pretty much covers it, though...
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(Hence the argument for a dire need for the new CSAR-X)
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