How Did the Hijackers Find the Pentagon, Anyway?

Courtesy of Caustic Logic over at his blog, and his uber cool ( ) graphic of the flight path of Flight 77, I have a rather serious question that as yet, no-one seems to have really addressed.

Just how did a box-cutter wielding psycho-hijacker know where to aim the aircraft after he'd taken it over?

After he had completed his 180 to head East (0855-0859) , he then corrected (0906) to head almost directly for the Pentagon. For the next 25 minutes, he flies on an almost constant heading, straight for the Pentagon! He doesn't deviate from this heading until around 0930 when presumably he becomes visual with the Pentagon.

He had 30 minutes (or 250 miles or so) to end up sufficiently north/south to get lost, and lose time finding something to tell him where he is, and how to find the Pentagon.

Some argue that the turn he made to hit the Pentagon was virtually impossible (I argue this point, but that is for another thread). If that is argued as impossible, just how did he figure out the heading to fly to the Pentagon shortly after he'd hijacked the aircraft??

[edit on 27-8-2007 by mirageofdeceit]

Simple answer. GPS. Modern airliners have GPS intergrated into their autopilot. All you need is a good map to figure out the coordinates. For another thread it took me 30 seconds to find the approach plates for Washington National airport. The GPS coordinates were on the plate. Use the approach to runway 17 and you literally can't miss the Pentagon.

The 757 he was flying wasn't equipped with GPS (unless you are suggesting he had a hand-held GPS with him?).

[edit on 27-8-2007 by mirageofdeceit]

Originally posted by mirageofdeceit
The 757 he was flying wasn't equipped with GPS (unless you are suggesting he had a hand-held GPS with him?).

[edit on 27-8-2007 by mirageofdeceit]

Really? I thought that it was mandatory. May I ask how you know this?

GPS plus it's really big and easy to see.

Have you ever flown into Reagan airport? You can see it while you land there.

Oh my God. Are there still people who think there were hijackings on 9/11?

Because the aircraft was built in 1996 and GPS wasn't an option at that time. It could be retro-fitted, but it was determined that this aircraft was never retro-fitted with it. It was a factory-fit option for new builds, but not all airlines took the option even then.

[edit on 27-8-2007 by mirageofdeceit]

Have you ever flown into Reagan airport? You can see it while you land there.

No, but I've got an idea what it looks like on approach.

Remember - he made the turn towards it whilst he was still 250 miles away from it! Too far to see.

Originally posted by mirageofdeceit
The 757 he was flying wasn't equipped with GPS (unless you are suggesting he had a hand-held GPS with him?).

[edit on 27-8-2007 by mirageofdeceit]

There are other ways to obtain accurate direction that you are heading and it always ain't GPS.

www.ntsb.gov...

D. NAVIGATION SYSTEMS DESCRIPTION AND ACTIVITY
The Boeing 757 keeps track of its own position using the Inertial Navigation System (INS),
which uses acceleration sensors to calculate the motion of the airplane over the ground. The
INS position calculation is periodically updated and corrected using data from ground based
radio navigation stations, called “very high frequency omnirange stations” (VORs). By tuning
a receiver to the signals broadcast from a VOR, the bearing from the airplane to the VOR
can be determined. Tuning in two or more stations and knowing the positions of each, a fix
of the airplane position can be obtained.
The 757 has two VOR receivers. The crew can manually tune each of these receivers to a
desired station (provided the station is in range), and view the airplane’s bearing relative to
the station on a special display mode on the Electronic Horizontal Situation Indicator (EHSI).
This mode is most often used when the crew wants to fly either towards or away from the
selected VOR station, along a specific bearing or “radial” to or from the station. In other
modes, the airplane will automatically tune in VOR stations along the airplane’s route in
order to obtain position fixes. The system generally selects stations whose bearings from the
airplane differ by about 90 degrees; this configuration results in the most accurate position
fixes.

I'll take that as a valid reason! (I already knew that anyway - and it is IRS = Inertial Reference System ). INS is what was used on the 707s.

Here is a rough plot of the flight path of Flight 77 over a satellite map (Google Earth).

Yellow = normal flight path
Blue = Hijacked Turn
Red = "I can see the Pentagon from here!"

Hopefully this puts some scale to what we're discussing here. Compare this to CLs map.

i167.photobucket.com...

[edit on 27-8-2007 by mirageofdeceit]

Mod Edit: Image Size – Please Review This Link.

[edit on 27/8/2007 by Mirthful Me]

This is looking more and more like a set up by the us goverment and i think more americans need to question thier goverment and not be be so blinded by patriotism.

I think there are MORE than enough people who question the official story of 9/11 in some aspect... we are just not getting any answers and I really do not think we ever will.

Originally posted by mirageofdeceit
Because the aircraft was built in 1996 and GPS wasn't an option at that time. It could be retro-fitted, but it was determined that this aircraft was never retro-fitted with it. It was a factory-fit option for new builds, but not all airlines took the option even then.

[edit on 27-8-2007 by mirageofdeceit]

I wasn't doubting you. I just wanted more info. My best guess would be that they flew VOR radials using DME. INS is difficult at best and the majority of their experience was with smaller aircraft. The course of Flight 93 took them right over the VOR station in Elwood City, PA. This is why there was a voluntary evacuation of the US Steel building in Pittsburgh.

[edit on 27-8-2007 by JIMC5499]

So debunkers let me get this straight:

The hijackers are flying towards the pentagon but decide to make a 330 degree turn to re-align the plane to hit the one and only side of the pentagon that just recently got reinforced just in case of an attack on said pentagon. Said hijackers, instead of doing the most obvious bonzai straight dive into this penta-gon, decide that it would be easier to fly in feet above the penta-gon lawn to hit the only reinforced section of the penta-gon causing the least amount of damage to said penta-gon possible.

Yeah, that's believeable.

Are you people beyond gullible?

Are you people even smart enough to discern a Spielberg movie from the real world?

Are you people beyond gullible?

No.

I'd already written this post once but lost the damn thing.

There is no suggestion he used VORs as the FDR data shows auto tuning behavior (you have to look quite a way back through the data to see this). It will attempt to tune box 1 to an on-track DME, and box 2 to an off-track DME (or as close as it can). As the aircraft flies past a DME, it will tune a DME ahead.

DCA VOR (the most likely choice as it is just 1.5 nm away from the Pentagon, thus the most accurate) doesn't get tuned until around around 30nm out (IIRC). You can check the FDR data for this.

A closer look at the DME shows that box 2 is tuned to some DME station that doesn't exist anywhere within 5nm of the Pentagon (and as I covered at the time - this does not even account for a secret DME at the Whitehouse as it is too far away). This led me to start to think that the FDR data was not all it seemed, as even whilst some people would argue the speed of the aircraft was very fast, this actually wouldn't affect the DME update rate either in the flight deck or on the FDR, as the FDR simply records what it is at that moment (as if you'd taken a photograph of all the flight instruments - they'd read what they were reading at the time you pushed the shutter release).

So that out-rules VORs/DMEs.

He didn't compute a straight line to the Pentagon based off present position and the position of the Pentagon - here is the formula for that:

Source

Rhumb lines

A ‘rhumb line’ (or loxodrome) is a path of constant bearing, which crosses all meridians at the same angle.

Sailors used to navigate along rhumb lines since it is easier to follow a constant compass bearing than to constantly adjust the bearing as is needed to follow a great circle. Rhumb lines are straight lines on a Mercator Projection map.

Formula: Δφ = ln(tan(lat2/2+π/4)/tan(lat1/2+π/4))
if E:W line q = cos(lat1) (length of a circle of latitude)
otherwise q = Δlat/Δφ
d = √[Δlat² + q².Δlon²].R
θ = atan2(Δlon, Δφ)
where ln is natural log, Δlon is taking shortest route (

Originally posted by Conundrum04
So debunkers let me get this straight:

The hijackers are flying towards the pentagon but decide to make a 330 degree turn to re-align the plane to hit the one and only side of the pentagon that just recently got reinforced just in case of an attack on said pentagon. Said hijackers, instead of doing the most obvious bonzai straight dive into this penta-gon, decide that it would be easier to fly in feet above the penta-gon lawn to hit the only reinforced section of the penta-gon causing the least amount of damage to said penta-gon possible.

Yeah, that's believeable.

Are you people beyond gullible?

Are you people even smart enough to discern a Spielberg movie from the real world?

The highjackers made the turn because when they were first able to spot the Pentagon they were at 7,000 feet.

They hit the side of the Pentagon that they hit because that was the side of the Pentagon that was facing them when they hit it.

originally posted by conundrum04

The hijackers are flying towards the pentagon but decide to make a 330 degree turn to re-align the plane to hit the one and only side of the pentagon that just recently got reinforced just in case of an attack on said pentagon. Said hijackers, instead of doing the most obvious bonzai straight dive into this penta-gon, decide that it would be easier to fly in feet above the penta-gon lawn to hit the only reinforced section of the penta-gon causing the least amount of damage to said penta-gon possible.

Remember conundrum04, Hani Hanjour had around 600 hours of flying time. He also had instrument flight training and I believe twin-engine turbine time. Maybe the experience he had would lead him to believe that he couldn't pull off diving a 757 into the Pentagon from several thousand feet.

Another thing, if it was an experienced pilot, F-16, A-3, cruise missile, Global Hawk or hologram, why would they intentionally fly over the Pentagon on their way into town and risk exposing themselves? Just curious.

Originally posted by Conundrum04
...to hit the only reinforced section of the penta-gon causing the least amount of damage to said penta-gon possible.

As you'll recall, the impact zone was completely destroyed. I'm trying to imagine what more damage could have been caused.

Originally posted by mirageofdeceit
Was a skilled pilot flying, and not a hijacker? Well, given the altimeter reset on the way down, this is likely. Whoever it was, it wasn't this incompetent hijacker that we're told was flying.

Oh, c'mon, Mirage.. Whoever told you that Hani Hanjour was an "incompetent hijacker"?

The plane was hijacked, and Hanjour was given the controls to pilot the plane into the Pentagon at 9:37 A.M. Hanjour obtained a commercial pilot's certificate in 1999 and according to the chief instructor, "Despite Hanjour's poor reviews, he did have some ability as a pilot." and "There's no doubt in my mind that once that (hijacked jet) got going, he could have pointed that plane at a building and hit it," he said.

en.wikipedia.org...

[edit on 27-8-2007 by Tuning Spork]

Why not just head straight to the whitehouse... it was within sight.