Swissgabe From Switzerland, joined Jan 2000, 5265 posts, RR: 36 Posted (7 years 2 months 5 days 12 hours ago) and read 10259 times:
I understand, that at the time when the 720 was available, there was already the Boeing 707-120 and -320 in service (or at least available for sale).
Why did Boeing produce an aircraft with a much smaller range and with lower speed. Fuelburn was a bit lower with the 720 as it had a capacity of arouns 20 pax less than the 707. Did the 707 indeed fly before the 720?
Smooth as silk - Royal Orchid Service /// Suid-Afrikaanse Lugdiens - Springbok
RedFlyer From United States of America, joined Feb 2005, 4181 posts, RR: 30 Reply 1, posted (7 years 2 months 5 days 12 hours ago) and read 10237 times:
Quoting Swissgabe (Thread starter): Why did Boeing produce an aircraft with a much smaller range and with lower speed.
At a time when the 707 was the only commercial jet Boeing had built, it was simply relying on it to address a different segment of the commercial market. Specifically, it was trying to shoe-horn a 707 derivative to meet airline requests for a smaller jet to serve smaller passenger markets. In the end, it wasn't a very successful attempt (it didn't completely address all requirements as it was simply too big) and directly resulted in the development of the 727.
CV990 From , joined Dec 1969, posts, RR: Reply 2, posted (7 years 2 months 5 days 12 hours ago) and read 10227 times:
Hi Swissgabe!
No, no, the B720 didn't have lower speed, infact the Boeing 720 was one of the fastest airliners at that time with the CV880 and CV990.
Boeing built the 720 to catch the market for some airliners that needed a jet to routes with medium capacity were the 707 or the DC-8 were too big, and also to fight Convair with their CV880 model.
And you know Boeing almost "burned out" the 720.....if they didn't catch UA order. Until that point Boeing was seriously considering to stop that project because Convair already had two big orders, one from DL and one from TW and Convair was in very, very good position to get UA, but at last minute Boeing gave a "great proposal" to UA and UA ordered it!!! Then other big orders came like AA, CO, Western, NW and then Boeing also got some airlines from outside USA that were thinking about starting jet flights with a more modest and cheap airplane like PIA, SV, ET, EL AL, Avianca!
The lesson of the Boeing 720 is the fact that after they came out with this model latter paid back because many of those small airlines that ordered the 720 actually got other Boeing models!
regards
DeltaRules From United States of America, joined Sep 2001, 3625 posts, RR: 11 Reply 3, posted (7 years 2 months 5 days 12 hours ago) and read 10097 times:
FLFlyGuy From United States of America, joined May 2004, 238 posts, RR: 3 Reply 4, posted (7 years 2 months 5 days 10 hours ago) and read 9925 times:
If I remember correctly the "720" designation was the result of a request by United. United had already ordered the DC-8. In addition to those aircraft, they needed to order jets for smaller routes. Originally, the 720 was to be called the 707-XXX (I don't remember the suffix). United, however, was concerned that if they bought something called a "707", it would be perceived as admitting that the DC-8's were a mistake.
Therefore, Boeing called it the 720, giving United the opportunity to tout it as a "new model" when in reality it was a 707 derivative.
The views expressed are my own, and not necessarily those of my employer.
Stirling From Italy, joined Jun 2004, 3943 posts, RR: 27 Reply 5, posted (7 years 2 months 5 days 9 hours ago) and read 9790 times:
Quoting FLFlyGuy (Reply 4): United, however, was concerned that if they bought something called a "707", it would be perceived as admitting that the DC-8's were a mistake.
And a big "mistake" it would have been, the United order for 30 DC-8s was at the time the largest commercial airline order ever, at $175 million.
Quoting FLFlyGuy (Reply 4): Originally, the 720 was to be called the 707-XXX (I don't remember the suffix).
That would have been the 707-020.
MTOW and fuel capacity were less than that of the 707-120, as well as being 8ft shorter for a 2-class capacity of 112 or single-class of 149.
But the major change centered on the wings. The 720 came with full-span leading edge flaps, and modifications to the area where the wing met the fuselage..increased sweep, which increased wing area, but decreased the thickness/chord ratio.....uh, simply, it was more aerodynamic allowing for higher cruising speeds.
So we actually had a better bird than the 707-100...albeit smaller. United, in the days when airlines marketed their airplanes as much as any other aspect of the service, didn't want to appear in the publics eye of having an inferior aircraft compared to the -100s and -200s out at the time, when in their eyes they felt the 720 was an improvement, demanded a different designation from Boeing, and got it.
The 720 was actually 2 aircraft, the original "720", and the improved "720B" first flown by American.
The original 720 came with PW JT3D-1 12,000lb thrust Turbojets...the later 720B had the JT3C-7 17,000lb thrust Turbojets. That's a big increase, about 40% more power.
The aircraft also had a higher MTOW and MZFW...that gave the 720B 45% more payload capacity, but more specifically, suited the 720B for short-haul services.
The new Turbofans increased the power-to-weight ratio, resulting in the shortest takeoff roll of any 707 derived aircraft.
Many earlier Turbojet models were later converted to Turbofans
It was known as a "Bargain Basement Jet", and this is what killed Convair, along with Boeings ability to offer a "family" of aircraft suited to each mission.
The 720B established the customer base for the 727 which went on to become the best selling jetliner of its time.
Quoting RedFlyer (Reply 1): Specifically, it was trying to shoe-horn a 707 derivative to meet airline requests for a smaller jet to serve smaller passenger markets. In the end, it wasn't a very successful attempt (it didn't completely address all requirements as it was simply too big) and directly resulted in the development of the 727.
TS-IOR From Tunisia, joined Oct 2001, 3306 posts, RR: 7 Reply 6, posted (7 years 2 months 5 days 9 hours ago) and read 9750 times:
I know very well the B720s of Conair Scandinavia. This type made the good days of this airline. Also my father told me that TWA used to fly NYC-TUN via MAD with B720s.
Kellmark From United States of America, joined Dec 2000, 670 posts, RR: 8 Reply 7, posted (7 years 2 months 5 days 9 hours ago) and read 9689 times:
I remember the B720s that we had at Eastern with the"straight-pipe" engines. They were numbered a/c 701-715. I flew on them as a passenger a number of times. The pilots liked them except that they were definitely underpowered. It took them awhile to climb to altitude. The 720B was definietly the better aircraft.
CF-CPI From Canada, joined Nov 2000, 855 posts, RR: 0 Reply 8, posted (7 years 2 months 5 days 9 hours ago) and read 9689 times:
I never realized that the turbofans gave that much of a boost.
I did hear some stories about the original turbojet variant. At Braniff they used to joke that it "wouldn't taxi over a wet cigarette butt" and takeoffs from high-altitude Mexico City were 'hair raising'.
No wonder the conversions were popular. Although Braniff never converted theirs, they did end up with some of Qantas' 707-138Bs, which hauled ass and was similar in size to the 720.
Cf6ppe From United States of America, joined Mar 2006, 309 posts, RR: 0 Reply 9, posted (7 years 2 months 5 days 9 hours ago) and read 9617 times:
Quoting Stirling (Reply 5): The original 720 came with PW JT3D-1 12,000lb thrust Turbojets...the later 720B had the JT3C-7 17,000lb thrust Turbojets. That's a big increase, about 40% more power.
Very good post, but.... the
The B720's came with the JT3C-7 (turbo-jet) powerplants.
and
The B720B's came with the JT3D-1 (turbo-fan) powerplants.
I've ridden on both the straight pipe and "B" versions. The straight pipe versions took a lot of runway and low fences, while the "B" versions were at 1,500 feet by midfield...
Gross weight for the 720 was about 230,000 pounds and 235,000 pounds for the 720B's.
Isitsafenow From United States of America, joined Feb 2004, 4984 posts, RR: 26 Reply 10, posted (7 years 2 months 5 days 8 hours ago) and read 9515 times:
Quoting Kellmark (Reply 7): I remember the B720s that we had at Eastern
Eastern had Boeing install two exit windows over the wing of their
720's...just like the exit windows on the 707. All other 720's had one exit window over the wing.
TWA 720B's were leased as a test and to compare with the 880. TWA changed the lease to a BUY but on 727-100's and turn the 720B's back to Boeing which did sell 3, and perhaps all four, to Northwest.
Quoting FLFlyGuy (Reply 4): Therefore, Boeing called it the 720, giving United the opportunity to tout it as a "new model" when in reality it was a 707 derivative.
I heard that story too... Its like later in time, Northwest's Donald Nyrop telling Donald Douglas to change the DC-10-20 to model 40 because it sounded newer then the DC-10 model 30...
safe
If two people agree on EVERYTHING, then one isn't necessary.
Stirling From Italy, joined Jun 2004, 3943 posts, RR: 27 Reply 11, posted (7 years 2 months 5 days 7 hours ago) and read 9431 times:
Quoting Cf6ppe (Reply 9): Very good post, but.... the
The B720's came with the JT3C-7 (turbo-jet) powerplants.
and
The B720B's came with the JT3D-1 (turbo-fan) powerplants
You're right.....my little rhyme that I use to remember failed me..."Cee the jet? It's Dee Fan" I know, silly, but its how I remember things..."C" for the Turbojet, "D" for the Turbofan...as in JT3C-X and JT3D-X. Thanks for catching it.
Quoting TS-IOR (Reply 6): TWA used to fly NYC-TUN via MAD with B720s.
Really?
Quoting CF-CPI (Reply 8): Although Braniff never converted theirs, they did end up with some of Qantas' 707-138Bs, which hauled ass and was similar in size to the 720.
It was 2 feet shorter than the 720, but its MTOW was 22,000lbs greater.
707-120 144 ft MTOW 257,000
707-220 144 ft MTOW 247,000
707-320 152 ft MTOW 312,000/331,000B/334,000C
707-420 152 ft MTOW 312,000
707-138 134 ft MTOW 247,000/257,000B
720-020 136 ft MTOW 229,000/235,000B
707s that never were....
The 707-620 would have retained the -320Bs MTOW of around 330,000 but the fuselage would have been stretched 25+ feet....if they could have figured out the landing gear issue. Because the aircraft sat lower to the ground, unlike the DC8 which sat higher, any more stretching to the 707 would have resulted in tail strikes...unless the gear was modified.
Another proposal was the 707-820, around 40 feet longer than the -320, with a wingspan 10 feet wider, it would have had a MTOW of 410,000....for a capacity of about 275. Again, the landing gear issues squelched that in addition to a complete re-think of the flap system..
I am thinking that if they gone ahead, they would have also found out they were going to need an entirely new wing as well, so either way, the -800 was doomed.
I have no idea where the -500 went.
The -700 was a CFM56 testbed. The aircraft was later refitted back with -320 powerplants and delivered to the Morrocan government.
Duke From Canada, joined Sep 1999, 1138 posts, RR: 2 Reply 12, posted (7 years 2 months 5 days 7 hours ago) and read 9343 times:
Yes, the original designation was going to be 707-000, or rather -020 according to the normal commercial designation system for the 707. It is also interesting that wing modifications from the 720 were re-incorporated into the turbofan 707-120B.
JDD1 From United Kingdom, joined Jan 2005, 94 posts, RR: 2 Reply 14, posted (7 years 2 months 5 days 6 hours ago) and read 9253 times:
I believe the 720 was introduced specifically to kill the Convair 880 and 990, which it did.
Boeing later used the same tactics when they introduced the 747SP to counteract the DC10-30 in South Africa (I think) and the 737-600 to fight off the MD-90 at SAS, which killed the MD-90 and MDC.
Qantas also had 720s. I flew from LHR to SYD in one in 1964 and can remember the Captain telling me that it was "a bit of a hot rod". We could visit the cockpit in those days.
Sllevin From United States of America, joined Jan 2002, 3376 posts, RR: 6 Reply 15, posted (7 years 2 months 5 days 5 hours ago) and read 9187 times:
Quoting Kellmark (Reply 7): I remember the B720s that we had at Eastern with the"straight-pipe" engines.
IIRC, those were also the only 720's with dual overwing emergency exits.
Quoting JDD1 (Reply 14): I believe the 720 was introduced specifically to kill the Convair 880 and 990, which it did.
That's the core reason for the 720. Boeing really, really, REALLY didn't want Convair to break into the business. Rumors were that they sold United the birds at cost just to keep the order from going to Convair.
Stirling From Italy, joined Jun 2004, 3943 posts, RR: 27 Reply 16, posted (7 years 2 months 5 days 5 hours ago) and read 9155 times:
Quoting JDD1 (Reply 14): Qantas also had 720s. I flew from LHR to SYD in one in 1964 and can remember the Captain telling me that it was "a bit of a hot rod". We could visit the cockpit in those days.
Sure you don't mean the -138B....it was certainly referred to as a "hotrod" many times. The moniker can be found in many publications that refer to QANTAS' special variant of the 707. But nowhere can I find any mention of a 720 being ever operated by QANTAS.
The 707 variants used by QANTAS were -138Bs, -338Cs, and a single -349, an original Flying Tigers aircraft operated from 1970 to 1973.
QANTAS operated 14 707 variants over its lifetime as far as I can tell.
RandyWaldron From United States of America, joined Mar 2006, 324 posts, RR: 3 Reply 17, posted (7 years 2 months 5 days 1 hour ago) and read 7440 times:
Incidentally enough, I just found an old book of mine just the other day in a stack of junk in my basement, entitled: "The Boeing 707 & 702" by George W. Clearley - it's fairly old but is very detailed about the 707/720's history.
Quoting Swissgabe (Thread starter): Why did Boeing produce an aircraft with a much smaller range and with lower speed.
The book says: "The Boeing 720 was designed and developed to operate over shorter state length flight segments than the 707 and was considered a medium range aircraft."
Quoting Swissgabe (Thread starter): Did the 707 indeed fly before the 720? Yes. The first variant of the 707, the Dash 80, flew on 7/15/54. The first 720 flew on 11/23/59.
BTCCMan From , joined Dec 1969, posts, RR: Reply 18, posted (7 years 2 months 5 days 1 hour ago) and read 7235 times:
Quoting TS-IOR (Reply 6): I know very well the B720s of Conair Scandinavia. This type made the good days of this airline. Also my father told me that TWA used to fly NYC-TUN via MAD with B720s.
Oops - TW never had 720s...
Quoting Stirling (Reply 16): Quoting JDD1 (Reply 14):
Qantas also had 720s. I flew from LHR to SYD in one in 1964 and can remember the Captain telling me that it was "a bit of a hot rod". We could visit the cockpit in those days.
StealthZ From Australia, joined Feb 2005, 5448 posts, RR: 48 Reply 19, posted (7 years 2 months 5 days 1 hour ago) and read 7157 times:
Quoting RandyWaldron (Reply 17): According to the book, "When the 720 was first publicly announced in July 1957, it was known as the Boeing 717...."
And that may be a mistake in the book. IIRC the "real" Boeing 717 was the company designation for the KC-135.
Quoting JDD1 (Reply 14): Qantas also had 720s. I flew from LHR to SYD in one in 1964 and can remember the Captain telling me that it was "a bit of a hot rod". We could visit the cockpit in those days.
I don't believe so, I am fairly familiar with the 707 variants that Qantas operated and I do not think there were ever any 720s, perhaps a short term lease or charter for a MX or capacity issue but I doubt it! In those days SIN-SYD was Long Haul for a 707, A 720 from LHR to SYD would be a "stopping all stations" ride
If your camera sends text messages, that could explain why your photos are rubbish!
RedFlyer From United States of America, joined Feb 2005, 4181 posts, RR: 30 Reply 20, posted (7 years 2 months 5 days ago) and read 6654 times:
Quoting StealthZ (Reply 19): And that may be a mistake in the book. IIRC the "real" Boeing 717 was the company designation for the KC-135.
It may not have been a publishing "mistake". Since the "717" nomenclature was not used, especially since the designation morphed into the KC-135, it could very well have been available for use by a civilian model. Afterall, isn't that why the 717 designation was eventually assigned to the former MD-95?
But here is the weird thing, they were ordered by TW, but the customer code they were delivered with was -051B....and not -031B as one would associate with TW Boeing orders.
NW didn't keep them much longer...selling them off to Monarch (791-793) and Maersk (794).
3 were cannabalized for USAF KC-135 program, but N784TW is extant and alive, currently with Honeywell as N720H in Phoenix!
StealthZ From Australia, joined Feb 2005, 5448 posts, RR: 48 Reply 23, posted (7 years 2 months 4 days 23 hours ago) and read 6387 times:
Quoting RedFlyer (Reply 20): It may not have been a publishing "mistake". Since the "717" nomenclature was not used, especially since the designation morphed into the KC-135, it could very well have been available for use by a civilian model. Afterall, isn't that why the 717 designation was eventually assigned to the former MD-95?
KC-135A Boeing Model #717-100A, -146, -148
KC-135B Boeing Model #717-166
C-135A Boeing Model #717-157
C-135B Boeing Model #717-157
C-135F Boeing Model #717-164
As this was an active production production program at the time the 720 was being developed it would be unusual to adopt the designation for a quite different aircraft. When Boeing took over the MD-95 program the original 717 program was but a distant memory (except of course to those men & women of the UASF that still fly and maintain them)
Nomeclature morphed into KC-135, that is not quite correct, many aircraft are assigned a military designation by particular operators and there were many cases in US service in the past where the different services had different designations. These aircraft often still retain their manufacturers model codes within the company. Easily identifiable examples are the -
VC-25A -B747
C-32 -B757
C-40 -B737
C-9 -DC-9
E-8 J-Stars -B707 (mostly ex Qantas 707-338 actually)
C5 -L-500
C130 -L-100
[Edited 2006-04-18 05:27:45]
If your camera sends text messages, that could explain why your photos are rubbish!
26 RayChuang: If I remember correctly, the 707-138B was a unique model for QF that had quite long range needed for transpacific operations (I think they flew them S
28 Stirling: No. Delta did not order any 720s. Delta Air Transport of Belgium is close as you will get, operating an ex-UA bird in 1974. You are correct. 1972. Th
29 N49wa: I flew many times on Western's 720B's. One question has always puzzled me; why did some airlines have the trademark 707 type antenna on the 720's tail
30 RedFlyer: I should've known better than to pontificate on this site, where all manner of experts and -- I say this with utmost respect -- where aviation nerds
31 Stirling: Jan71....going to Great American Airways in Jan81
32 Grantcv: It seems that Boeing was trying to convince the world that the B720 was a completely new aircraft rather than yet another B707 derivative. I seem to r
33 BHMNONREV: Thank you sir!! I had forgotten about that one. For Zep afficianados out there, you will find several shots of this bird in "Hammer of the Gods", the
34 Broocy: Nearly so, but from Jon Proctor's excellent book "Boeing 720" he says that UA's William Patterson pushed for a new designation to save face given UA'
35 LongHauler: That antenna was an HF antenna. If like WA you needed HF communication, (for Hawaii flights) then it was installed. However, United did not fly their
36 Duke: A few miscellaneous answers to the above: 1. Stirling is right. Qantas flew the very similar-looking short-body 707-100, but never the 720. 2. At one
37 JDD1: Stirling and StealthZ I stand corrected, it must have been a 707-138B I was on, but to use your quote, it was a "stopping all stations" ride: LHR-IST-
38 Isitsafenow: The TWA 720B's Well, the four were leased from Boeing, turned back to Boeing, leased by NW then purchased by NW. The NW N numbers were N730US, N 731U
39 Stirling: I would sure love to know more about this!
40 Stirling: I remember I had Jon Proctor's email...I dropped him a line...he is a great source of TWA knowledge. For those of you who don't know, Jon Proctor is
41 RC135U: I noticed that a Jon Proctor was listed as a new member of A.net a couple of months back, so I'm sure he's following these threads.
42 Milesrich: UA introduced the 720 on June 5, 1960, and retired the last one in September of 1972. The entire fleet of 29 was stored, split between DEN, as the pic
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