Brownout Accidents Plague CSAR-X Helicopter

Note: This is an adaptation of a press release POGO put out this morning.

The H-47 Chinook clocked only 7 percent of all U.S. Army helicopter flight hours between February 2003 and June 2005, yet accounted for 30 percent of all brownout mishaps between fiscal years 2002 and 2005, Army data shows.  According to Aerospace Daily and Defense Report yesterday, "Congressional lawmakers are reviewing downwash data for the helicopters that competed for the U.S. Air Force's combat, search and rescue (CSAR-X) helicopter replacement fleet to make sure rescue operations can be done safely." As part of this review, Congress should also look at Army data which show that the Chinook disporportionately suffers accidents from brownout (swirling dust and sand) compared to the rest of the helicopter fleet.

Boeing's H-47 Chinook helicopter was selected for the $10 to $15 billion combat, search, and rescue (CSAR-X) contract last year, but the contract is being re-bid in response to protests by competition.

POGO recommends that the Air Force make a fair comparison of the bidder's proposals on the basis of this and all the other key performance parameters, and that the comparison and standards for comparison be made as transparent as possible to the bidders.

CSAR-X program documents clearly state the need for a helicopter which does not have a rotor downwash that will impede operations.  According to the June 16, 2005, Capability Development Document for Combat Search and Rescue Replacement Vehicle (CSAR-X)/Personnel Recovery Vehicle (PRV):

    The downwash produced by the CSAR-X (PRV), at mid-mission gross weight, in and around the recovery vehicle during a hover in all operational environments must not impede safe and successful recovery of isolated personnel. These environments include, but not limited to, heavily forested steep mountainous, smooth-level, rough-level, smooth-sloped, and roughsloped terrain in calm and high crosswind conditions. Loose particles such as tree limbs, sand, snow, water or rocks in the hover zone at mid-mission gross weights with SCL in Appendix G must not prevent the Recovery Team or injured and un-injured isolated personnel from conducting safe AIE operations (providing emergency life saving measures to isolated personnel, placement of a non-ambulatory personnel in a hoist recovery device, overland movement, self protection, communication, and swimming). (Emphasis added)

However, the Air Force seems to have ignored its own requirement when it picked the Chinook.

Despite the rotor downwash requirement, the initial competition picked a helicopter—Boeing’s  Chinook—that produces significant downwash, and is prone to accidents due to brownout (swirling sand and dust caused by downwash).  The May 2005 article “Brownout on the Battlefield,” in FlightFax, a magazine by the U.S. Army Combat Readiness Center,

    In the past 5 years, there have been 11 Class A, B, and C aviation accidents involving Chinook aircraft with brownouts being the trigger event.  These mishaps have resulted in 16 non-fatal injuries and equipment damage costs in excess of $37 million.

***

    All aircraft will kick up dust, but the Chinook produces the largest dust because of the size of its rotor system and its weight.  (Emphasis added)

A look at data compiled by the U.S. Army shows that the Chinook disproportionately suffers from brownout, and other mishaps and accidents when compared to the overall U.S. helicopter fleet.  Click here to see the data.

-- Nick Schwellenbach

Army Aircraft Mishaps/Accidents and Percentage of Chinook Accidents
U.S. ARMY BROWNOUT (BO) RELATED ACCIDENTS*
FY	C/MH- 47D/E BO Mishaps	All USA Helo BO Mishaps	H-47 % of All BO Mishaps
2005	1	3	33%
2004	2	8	25%
2003	4	22	18%
2002	5	8	63%
Total	12	41	29%
U.S. ARMY A, B, & C ACCIDENTS*
FY	C/MH- 47D/E Mishaps	All USA Helo Mishaps	H-47 % of All Mishaps
2005	15	107	14%
2004	15	108	14%
2003	15	125	12%
2002	21	124	17%
Total	66	464	14%
U.S. ARMY C/MH-47D/E DATA*
As of	Inventory of C/MH- 47D/E	All USA Helo	H-47 % of All USA Helo
2005	453	3786	12%
U.S. ARMY HELOs & C/MH-47D/E in Operation Iraqi Freedom**
Period	Inventory of C/MH- 47 D/E	All USA Helo	H-47 % of All USA Helo
Feb 2003 - June 2005	44	466	9%
U.S. ARMY HELOs in Operation Iraqi Freedom C/MH-47D/E DATA**
Period	Flight Hours C/MH-47D	Flight Hours All USA Helo	H-47 % of All USA Helo
Feb 2003 - June 2005	37522	537377	7%

*U.S. Army Safety Center Accident Data FY2002 - FY2005
**BGEN Sinclair APBI Briefing

Source: U.S. Army; chart prepared by Aerospace Daily & Defense Report, March 7, 2007, Volume 221, Issue 44.

Note: C/MH-47D/E refers to diferrent models of the Chinook airframe.

Comments

[Joe Katzman]

RE: is the Chinook in more frequent brownout situations - the answer is yes. The CH-47 (along with the CH-53E) has seen very disproportionate use in Afghanistan, due to the hot weather and high altitudes that rob helicopters of their lifting capacity. Which is why you don't see very many Blackhawks used as troop transports or supply carries in Afghanistan. Even the C-130E/H Hercs have problems there - and you won't like to hear this, but the C-130J can carry up to 3x more cargo in that theater after "hot and high" subtractions are factored in.

Given that this is also the theater in which one must expect the most brownouts (many of the Iraqi zones are not sandy), a higher brownout total is only to be expected. If you're serious about getting the best SAR helicopter, the data needs to be looked including helicopter flight-hours in Afghanistan, and then see how the CH-47 compares to the CH-53E in particular. Otherwise, it's very likely to be a false issue driven by other helicopters' LACK of capability.

Of course, if your SAR helicopter is going to be operating in those areas, and it must, it needs to have that lifting capacity too. Not to mention survivability (EH101's extra fuel tanks in the floor is fine for picking sailors out of the North Sea, but in a hot SAR combat zone I'd be very nervous - and their maintenance /safety record in Britain, Canada et. al. sucks), and redundancy (the H-92 has just two engines and verges on underpowered - how does that work for you in "hot and high" conditions like Afghanistan, or when an engine gets shot out?). Then there's the CH-47 (twin-rotor design allows precision maneuvers others can't match - but you still have to fit into small areas sometimes, least stealthy re: radar or noise, highest maintenance, can't travel on amphibious ships - but could 'lily pad hop' to/from one).

ALL of the CSAR-X candidates have significant negatives, in my opinion, and the V-22 would have been a lethally bad choice (terrible visibility due to few and small windows, no weapons coverage, huge downwash to the point of being dangerous, no autorotation). My personal take: the best aircraft for this mission would be a CH-53K "Pave Low-21" variant - but the USAF wants the helicopters much sooner than that... which means that unless they split the CSAR-X into 2 phases with potentially different winners, we're down to a choice of which sub-optimizations we decide we can live with.

That's why I'm not as surprised by the USAF's choice as many other people seem to be.

Given R&D to address the brownout issue via "Project Sandblaster" et. al., brownouts rank far lower on the list for me than other problems with the various designs (EH101's fuel tank placement and safety/maintenance record, H-92's questionable power level, H-47 least stealthy, and potentially slowest-deploying due to amphibious ship constraints).

Project Sandblaster:
http://www.defenseindustrydaily.com/2007/03/darpas-sandblaster-program-is-on/index.php

[Nick Schwellenbach]

FYI, POGO received the following anonymous message. But before you read it, let me respond to some of its charges.

"The information that I've read seems to be based on historical information, some of which seems to be dated."

Of course the information we presented is "historical," it happened in the past--between 2002 and 2005. However, the anonymous author's standards for something being "dated" seem to be extraordinarily high.

"If the the H-47 flew a higher number of its hours/missions where brown-outs were more likely to be an issue than the hours/missions of the other helos then it is very possible that the percentage to be disproportionate, and would make sense."

We presented all the data we have, which should lead to the question you suggest--does the Chinook disproprortionately suffer from brownout accidents than other helos because it is put into tougher situations more often? A good question, and one we would like to see answered as well, which is why we made this post.

I'd also like to suggest that folks check out a comment on the "CSAR-X Tips Welcome" post:

"Now there are plenty of reasons that the Chinook is the incorrect choice as a CSAR-X platform, but downwash probably isn't one of them unless you examine closely how hard it is to safely accomplish a litter hoist recovery through the side door of a 47."

The following are the anonymous comments we received:

Concerning the CSAR-X program article....

How about showing data indicating each of the missions of the brown-out accidents in relation to the the accidents and flight hours.

If the the H-47 flew a higher number of its hours/missions where brown-outs were more likely to be an issue than the hours/missions of the other helos then it is very possible that the percentage to be disproportionate, and would make sense. Without this data, you are skewing the facts and make is appear that you are in someone's pocket for doing so.

You don't show the proposal test data results for the down-wash yet you seem to indicate that the Air Force disregarded this information in making their decisions. How can you say that? The information that I've read seems to be based on historical information, some of which seems to be dated.

Additionally, perhaps you could review the footage of the Mt. Hood rescue attempts where the H-47, on national television dropped rescuers at the top of the mountain and hovered in the area, at high altitude, for quite a long period of time. I don't recall the rescuers being blown off the top of the mountain as they would surely have been if the down-wash was to an extent to prevent a safe attempt at rescue. Seems that it was quite successful in the safe delivery and extraction of the rescue team.

Thanks for listening. Let's hope you have enough integrity to go back and show all of the data, and if you don't have the data, at least mention that these figures could be skewed by a disproportionate number of missions being undertaken that could cause these facts to appear as they do.