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RIP Father of String Sails, Dr. Jerry Milgram


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Sounds like he had his hand in a lot of things... and had a pretty good run!

 

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MILGRAM, Jerome H. Age 83, passed away December 20, 2021, at his home in Winchester, Massachusetts, with his family by his side. Jerry was the W. I. Koch Professor of Marine Technology at the Massachusetts Institute of Technology (MIT) where he taught since 1970. Jerry was a member of the National Academy of Engineers and recipient of the 2017 Gibbs Brothers Medal (awarded for outstanding contributions in the field of naval architecture and marine engineering). Jerry contributed to the development of many technologies associated with oceans: boat design, oil spill clean-up, tug and tow technology, underwater submersibles, and even holograms that detected plankton. He often worked closely with the United States Navy and the Coast Guard. Jerry was the design director and chief computer modeler for America3, which won the America's Cup in 1992 by using a more scientific approach to the design of racing yachts. Jerry was born in Melrose Park, Pennsylvania, on September 23, 1938, the oldest child of Samuel Milgram and Fannie (Marmor) Milgram. He loved sailing from an early age, and was captain of the sailing team at MIT, where he received his undergraduate degree in 1961 and his PhD in 1965. Even while teaching and doing research he loved outdoor activities including cycling, and sailing his self-designed boat, the Cascade. Jerry is survived by his wife, Robin (Horowitz) Milgram, his stepson and daughter-in law, Eben and Uromi Manage Goodale, his grandson, David Parakrama Goodale, his sister Linda (Milgram) Becker, his nephew Eric Ring and his wife Melissa Wallen, his late nephew Steven Ring and his wife Mary Ring, and their children, Andrew and Melissa. Jerry was kind, smart and witty. He was a devoted husband, and loving brother, father, uncle and grandfather, who will be deeply missed. An online Memorial Service, hosted by Eben and Eric, will occur on January 8, 2022. In lieu of flowers, the family asks that donations be made to Oceana (www.oceana.org), which is the largest international ocean conservation organization, or to MIT (giving.mit.edu).

 

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I have to take exception to calling Tape Drive Sails ugly. When we got Tape Drives in black and clear on our racing trimaran we sort of became the 'poster boat' and had some great Billy Black photos used in the magazine articles. We won a lot of races with them and came to love them and we called those sails our 'Fredricks of Holllywood' sails because you could sort of see right through them like fine lingerie...

    I also never thought that CASCADE was ugly either, just a different sort of mind set! RIP Jerry

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I worked with him in the early '90's on a ship wake program for the Navy.  He was different/eccentric.  His perpetual tie clip was what most of us call a paper clip.  He worked on Koch's AC design team and at one point was kicked out of a meeting.  Saw him maybe a month after they won and congratulated him on their victory, he didn't want to talk about it.  I guess Bill was trying to make it up to him by endowing the chair at MIT.

I'm really pleased to have crossed paths, he was a brilliant mind and passionate about his work and the students he nurtured.

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Ullman Tape Drive main in the Malacca Strait negated any possibility of anonymity ......

 

anonymous_190523-800x450.jpg

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7 hours ago, silent bob said:

I have to say, Cascade was as ugly as Tape Drive.  Both very good ideas, just not well implemented.  Vale, Mr. Milgram. Your ideas did make sailing better!  

Ugly or not, it won a lot of races.

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1 hour ago, ryley said:

Ugly or not, it won a lot of races.

So many that the only way not to lose to Cascade was to give it a rating penalty.....because, well just because it was faster than its measurement said it should be.

If you wanted pretty and slow, there were any number of designers .

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I always wondered how that oinker did against other 37 footers boat for boat.

A trick rating is one thing but actual boat speed???

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The IOR really favoured big headsails and (almost) ignored mizzen sails. So it must have rated very, very low. The hull wasn't an IOR favoured shape however.

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40 minutes ago, SloopJonB said:

I always wondered how that oinker did against other 37 footers boat for boat.

A trick rating is one thing but actual boat speed???

read this article: https://vault.si.com/vault/1973/03/12/sailing-up-a-squall

there's a portion where she is described as "maddeningly swift."

Here's an excerpt:

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On the whole the SORC weather favored Cascade, as her crew quickly conceded. When the wind is on her beam, she flies. On a beat or a dead run, she does not. Never did she have a breeze better suited to her than in the 176-mile Miami-Nassau. She waffled off the starting line last as usual, but as her staysail flapped up and bellied with the beamish southeasterly, she leaped ahead. Within 10 minutes she had Lightnin' abeam in her own Class E and was fast catching up with Muñequita, which had started a full 15 minutes earlier with Class D

That night, with Jerry Milgram in polite command, Cascade cruised across the Gulf Stream toward Great Isaac Light as if on holiday. All around, the winking running lights of competitors kept her crew company. At Isaac several boats were spotted sailing illegally toward shortcuts among the rocks—boats that later went unpenalized. When Cascade had committed her own costly error in the Fort Lauderdale race a boat named Devastator had promptly turned her in. Such is sailing.

 

 

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51 minutes ago, SloopJonB said:

I always wondered how that oinker did against other 37 footers boat for boat.

A trick rating is one thing but actual boat speed???

no idea of the time difference used in IOR

but the boat had a 22 rate vs 1 ton boats the same size rate 27.5

20% by raw numbers

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3 hours ago, Zonker said:

The IOR really favoured big headsails and (almost) ignored mizzen sails. So it must have rated very, very low. The hull wasn't an IOR favoured shape however.

A common myth that simply was not true.  IOR actually favoured big low AR mains.  What you say about the mizzen was true however.

Anyone who has played around with the IOR RSAT calculations will quickly realize how much it favoured big mains and smaller headsails.  At least with regards to actual sail area vs rated sail area.

Milgram took it one step further and eliminated the headsail altogether.  Combine that with the low rated area of a mizzen and indeed you end up with a very low RSAT.

IIRC, Cascade had a sail area of 800 sq ft but an IOR S of 300 sq ft.

The hull form itself contributed little or nothing to the low rating - it was all about rated sail area.  By the time IOR had finished somewhat arbitrarily penalizing her she rated 27, or just below One Ton level rather than just below the Half Ton level she was originally rated at.

However IOR didn't really fix the no-headsail loophole at that time, because just a few years later a rather large (27 ft) Cat sloop named L'Effraie  won the '76 Mini-Ton Worlds.  Quite handily IIRC.  She had a very typical looking IOR hull form for that era - albeit larger than pretty much all Quarter Tons and much larger than any Mini-Ton which were usually 22 ft LOA or thereabouts.

Below is L'Effraie (not Cascade).

Effraie-c.jpg

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Having never had to subject myself to the IOR rule, why did type formed IOR racers tend to tall skinny mains and huge overlapping genoas (in the earlier days of IOR)?

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4 hours ago, SloopJonB said:

I always wondered how that oinker did against other 37 footers boat for boat.

A trick rating is one thing but actual boat speed???

I would guess she would have similar speed to a One Ton of that era - once the sheets were used.

They would probably do a horizon job on her upwind and be faster DDW.

But on a beam reach, I suspect Cascade may have been faster having basically two mainsails.

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50 minutes ago, Zonker said:

Having never had to subject myself to the IOR rule, why did type formed IOR racers tend to tall skinny mains and huge overlapping genoas (in the earlier days of IOR)?

Following a winning trend I suspect. 

Or the designers felt the efficiency of such a rig more than compensated for the high rated sail area it incurred.  Or that MH rigs worked better for heavier boats

Recalling what I can about how IOR rated sail area:

 100% of the geometrical area of the genoa was used in the calculation.

Only 70% of the geometrical area of the main was used in the calculation.

An aspect ratio penalty was applied to both the genoa and main (may have been greater for the main - my mind is a bit hazy on this, but would explain lower AR mains)

There was an RSAF/RSAM calculation (can't remember what it was called)  applied to the combined  areas - where the larger the proportion of headsail area to mainsail area, the larger the multiplier.

So basically, headsail area got hit with a triple whammy in the S calculation.

I sailed on a local Ganbare 35 in the early 80's and struggled to keep up with the Mk II & III Peterson 35s in the light stuff.  Extended the boom and E by some 2.5 feet so actual main sail area increased by about 55 sq ft - but comparing the new IOR cert with the old one, RSAM went up by only 11 sq ft.

 

 

 

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Some kind soul scanned each page of Mk III, up to 1985. Read it at your peril. This is really simplified so bear with me if you have designed to the IOR Rule! I've only been exposed to it slightly. I may be cutting important corners

http://www.acmenovelties.net/sailing/ior_rule/

image.thumb.png.e24bc8f56f5159d8b237855169be6b71.png

I think the first formula SAM = 0.35 E P + 0.2 E (P - 2E) does underestimate real mainsail area considerably.

For example I have a E = 10 and P = 30.

SAM = 0.35 (10 x 30) + 0.2 x 10 (30 - 2 (10)) = 125 ft2. 

A plain triangle of E x P / 2 = 150 ft2

A real main, with roach will be maybe 12% more or 168 ft2 (~74%). The 12% might be a more modern figure where we are using longer battens. So probably 12m is correct = about 70% of actual area is rated.

(I am ignoring the Reduced Girth Factor etc correction assuming it wasn't usually  taken. Also ignoring Corrected E and P (EC PC) because they probably have to do with headboards and tack/clew offsets etc.

image.png.2e18fcfc166c082a47c7e2e03a42f117.png

I = 30, J = 10, LP = 15 

I 30
J 10
LP 15
   
RSAF 217.5

A genoa of those proportions would have a real area pretty close to the rated area.

I think where the big difference lies is a genoa is more efficient without a mast in front of it for equal amounts of sail area. So the rule type forms you toward big genoa + small main. So 12 metre is very correct - the main is less penalized.

In later years (Mk III version something or other or Mk IV) we started to see many more 7/8 rigs with bigger mains. That might have been because they finally realized they could make a more flexible main for trimming or that main area was under-rated.

(This probably also led to the skinny IOR masts where you were trying to make the mainsail as little shadowed by the mast as possible.)

A fascinating history lesson.

 

 

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Yeah Zonker, mainsail girth at the quarter heights was restricted to a percentage of E and was quite minimal, so not much roach.

Batten lengths were also restricted to % of E until mid 80's when they could go longer.

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2 hours ago, Zonker said:

Some kind soul scanned each page of Mk III, up to 1985. Read it at your peril. This is really simplified so bear with me if you have designed to the IOR Rule! I've only been exposed to it slightly. I may be cutting important corners

http://www.acmenovelties.net/sailing/ior_rule/

image.thumb.png.e24bc8f56f5159d8b237855169be6b71.png

I think the first formula SAM = 0.35 E P + 0.2 E (P - 2E) does underestimate real mainsail area considerably.

For example I have a E = 10 and P = 30.

SAM = 0.35 (10 x 30) + 0.2 x 10 (30 - 2 (10)) = 125 ft2. 

A plain triangle of E x P / 2 = 150 ft2

A real main, with roach will be maybe 12% more or 168 ft2 (~74%). The 12% might be a more modern figure where we are using longer battens. So probably 12m is correct = about 70% of actual area is rated.

(I am ignoring the Reduced Girth Factor etc correction assuming it wasn't usually  taken. Also ignoring Corrected E and P (EC PC) because they probably have to do with headboards and tack/clew offsets etc.

image.png.2e18fcfc166c082a47c7e2e03a42f117.png

I = 30, J = 10, LP = 15 

I 30
J 10
LP 15
   
RSAF 217.5

A genoa of those proportions would have a real area pretty close to the rated area.

I think where the big difference lies is a genoa is more efficient without a mast in front of it for equal amounts of sail area. So the rule type forms you toward big genoa + small main. So 12 metre is very correct - the main is less penalized.

In later years (Mk III version something or other or Mk IV) we started to see many more 7/8 rigs with bigger mains. That might have been because they finally realized they could make a more flexible main for trimming or that main area was under-rated.

(This probably also led to the skinny IOR masts where you were trying to make the mainsail as little shadowed by the mast as possible.)

A fascinating history lesson.

 

 

The first terms in calculating RSAM and RSAF were to determine the areas of the main and foresail.  But RSAM had a .35 multiplier while RSAF had the .5 multiplier.  Since you use .5bh to find the area of a triangle, they simplified it by using .35 rather than .7 x .5 for the main and .5  rather than 1 x .5 for the foresail.  The second part of the first term for RSAF (1.0+1.1*(LP-JC)/LP) was to account for the area of the overlap and typically came out as 1.33 IIRC

The second terms were the Aspect Ratio penalties (or adders) I mentioned in my previous post.  A bit primitive, but it at least partly took into account the efficiencies of a high AR sail plan.  For the main this was 0.2*EC*(PC - 2*E).  For the foresail it was 0.125*JC*(IC-2JC).  As a result a high AR main was penalized more heavily than a high AR foresail (.2 vs .125multiplier).  Hence IOR favoured a low AR main more than a low AR foresail.  At least as far as maximizing actual sail area vs rated sail area.  In your example, if you decrease P to 25 and increase E to 12, you get the same triangular area of 150 but SAM decreases from 125 to 107.4

Milgram and the French guy just took it to the logical extreme and eliminated the foresail altogether.  The rule said you must be rated with a mainsail - but where there is no provision for setting sails in the foretriangle, RSAF shall be zero.

On top of all this, elsewhere in the rule I believe you will find the part about a sliding scale penalty based on RSAF/RSAM

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Back to paying respect to Jerry Milgram.

I vaguely remember his name coming up in I think some Davidson Laboratory (Stevens Institute) publication in my Grandpa's library.

It could have been this one: https://books.google.com.fj/books?id=fVLuI07rKw4C&pg=PA538&dq=jerry+milgram+davidson+laboratory&hl=en&sa=X&ved=2ahUKEwijldyKnZr1AhWQwzgGHdZXCPAQ6AF6BAgJEAE#v=onepage&q=jerry milgram davidson laboratory&f=false

He must have been 32 or so, at the time. Way above my paygrade anyway. Perhaps more appropriate for SA is this obituary, one of many. A great man indeed: https://news.mit.edu/2022/professor-emeritus-jerome-milgram-dies-0104

Jerome-Milgram-bw.jpg.f26274a861f2ecc6155d5e9f153d0fdd.jpg

 

 

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