Re: NROL-20: 48 ft fairing

From: satcom (john@satcom.freeserve.co.uk)
Date: Wed Oct 19 2005 - 09:46:39 EDT

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    Hi Ted...... and list.
    
    
    As Ted has found in the past , sometimes the  mission patch can reveal some 
    info...
    
    Have a look at...
    http://mysite.wanadoo-members.co.uk/satcom_transits/B26patches.jpg 
    especially the one on the right.
    Are those just random stars , or do they hint at the satellite 
    constellations.
    
    Also , from the last launch.... (NROL 22 )
    http://mysite.wanadoo-members.co.uk/satcom_transits/NROL22.jpg
    
    
    
    
    John
    
    
    ----- Original Message ----- 
    From: "Ted Molczan" <seesat@rogers.com>
    To: <SeeSat-L@satobs.org>
    Sent: Wednesday, October 19, 2005 12:32 PM
    Subject: NROL-20: 48 ft fairing
    
    
    > The mysterious 76 ft fairing shrank yesterday to a perhaps equally 
    > mysterious 48
    > ft, as reported by Spaceflight Now:
    >
    > http://www.spaceflightnow.com/titan/b26/status.html
    >
    > "The rocket is sporting an unusual 48-foot long nose cone to protect its
    > clandestine National Reconnaissance Office payload during the ascent 
    > through the
    > atmosphere. The fairing started as a standard 76-foot shroud but was 
    > modified to
    > the shortened length, Smith said.
    >
    > A similar fairing was used in May 1999 when a Titan 4 launched from 
    > Vandenberg
    > carrying what hobbyist sky watchers consider to be a mysterious "stealth" 
    > spy
    > satellite."
    >
    > In order to understand the possible significance of the reported 48 ft 
    > fairing,
    > it is necessary to review the different types of Titan-IV fairings that 
    > have
    > flown from VAFB. What follows is my present understanding, subject to 
    > revision
    > as more is learned.
    >
    > For a long time, it was considered that VAFB payloads employed two lengths 
    > of
    > fairing:
    >
    > T-IV Type  Payload   Fairing     Orbit
    >   403     NOSS        56 ft   63.4 deg
    >   403     Lacrosse    66      57 or 68 deg
    >   404     KeyHole     66      98 deg
    >
    > In 1999 came the launch of the mysterious USA 144, on a 404B Titan, to a 
    > 63.4
    > deg orbit. Justin Ray, reporting for Florida Today at the time, learned
    > officially that the fairing had been 50 ft long. The launch occurred in 
    > the
    > middle of a foggy night (how appropriate!), and the only photo I had at 
    > the time
    > inadequately revealed the fairing, so I had no easy way to verify this.
    >
    > However, Phil Chien recalled that a 50 ft fairing had long been listed in 
    > the
    > T-IV's promotional literature. Indeed, an early T-IV brochure, kindly 
    > provided
    > by Phil, listed only a 50 ft fairing for the model 404, which was 
    > confusing,
    > since the KeyHole 404 launches to that time, were thought to have employed 
    > the
    > 66 ft fairing.
    >
    > Earlier this year, I made an effort to verify the fairing length of all 
    > past
    > T-IV launches for which I could locate a useable photo, which led to me 
    > this one
    > of USA 144:
    >
    > http://www.nro.gov/graphics/launch5_99.jpg
    >
    > Resolution and lighting are poor, but with moderate magnification and
    > brightness/contrast adjustment, I believe I can make out the boundary 
    > between
    > the vehicle and adapter (aka boat tail) section of the fairing, and the 
    > boundary
    > between the cylindrical and conical sections of the fairing. Likewise, I 
    > believe
    > I can adequately resolve the diameter of the cylindrical section. I get a 
    > ratio
    > of length to width of around 1.7, which when multiplied by the known 16.67 
    > ft
    > diameter, yields a length of 28.3 ft, which accounts for the boat tail and
    > cylindrical section. The conical section cannot be measured, but all of 
    > them are
    > 19.86 ft long, which brings the overall length to 48 ft - pretty close to 
    > the
    > reported 50 ft.
    >
    > In 2001 October, I learned of a new wrinkle in the story of VAFB fairings.
    > Charles Vick posted to FPSPACE that the fairings of the KeyHoles launched 
    > in
    > 1992, 1995 and 1996 had not been 66 ft, but rather 50 ft, which sat atop a
    > special 14 ft adapter he describes as a bucket, which was permanently 
    > attached
    > to the 2nd stage. This brought the overall length to just over 64 ft, 
    > which
    > could easily have been mistaken for a 66 ft fairing. Adding yet another 
    > wrinkle,
    > Charles also pointed out that the KeyHole launched in 2001 October was the 
    > first
    > to have an actual 66 ft fairing.
    >
    > In my exercise this year, I found that the pre-2001 KeyHole overall 
    > fairing
    > length was 62 ft, close to Charles Vick's value of 64 ft. This seemed to 
    > roughly
    > confirm that the fairing was 50 ft on top of a 14 ft bucket, which might 
    > explain
    > the confusing claim of 50 ft in the old T-IV brochure.
    >
    > Also, keeping in mind that the bucket was said to have remained attached 
    > to the
    > 2nd stage, it might explain why the 2nd stage of the 1996 KeyHole (96072B 
    > /
    > 24681) was so much brighter than other T-IV 2nd stages:
    >
    > http://satobs.org/seesat/Jan-1997/0003.html
    >
    > My analysis of launch photos also confirmed that the 2001 KeyHole launch
    > employed a 66 ft fairing.
    >
    > So, based on my present understanding of the fairings, I interpret the 
    > news of a
    > 48 ft fairing on today's scheduled  404B T-IV for launch, as follows:
    >
    > If photographs reveal an overall length of 48 ft, then perhaps the payload 
    > is a
    > Misty - the first to be targeted for one of the two standard KeyHole 
    > orbital
    > planes.
    >
    > If the overall length is around 62 to 64 ft, then it would appear to be a
    > regular, i.e. non-stealthy KeyHole, reverting to the pre-2001 fairing 
    > length.
    >
    > Ted Molczan
    >
    >
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