- Simple Intercept Missile Equation
- Simple Intercept Missile Examples
- Simple Intercept Missile System
- Simple Interceptmissile&turretbehaviour Demo Mac Os Downloads
- With the free demo software you can develop, save and document your projects (communication with hardware is not possible). Requires Mac OS X 10.6 Snow Leopard, Mac OS X Lion, Mac OS X Mountain Lion, Mac OS X Maveriks. TIA Selection Tool - quick, easy, smart TIA Selection Tool - quick, easy, smart.
- From Easy Grade Pro's straightforward interface you have quick and easy access to the following six tabs: Score, Attendance, Seating, Student, Assignment and Standard. Each grade book is designed to store numerous classes and subjects in more than one.
The lowest layer of OS X includes the kernel, drivers, and BSD portions of the system and is based primarily on open source technologies. OS X extends this low-level environment with several core infrastructure technologies that make it easier for you to develop software.
The Sprint was a two-stage, solid-fuel anti-ballistic missile (ABM), armed with a W66 enhanced-radiation thermonuclear warhead used by the United States Army.It was designed to intercept incoming reentry vehicles (RV) after they had descended below an altitude of about 60 kilometres (37 miles), where the thickening air stripped away any decoys or radar reflectors and exposed the RV to.
High-Level Features
The following sections describe features in the Kernel and Device Drivers layer of OS X.
XPC Interprocess Communication and Services
XPC is an OS X interprocess communication technology that complements App Sandbox by enabling privilege separation. Privilege separation, in turn, is a development strategy in which you divide an app into pieces according to the system resource access that each piece needs. The component pieces that you create are called XPC services.
You create an XPC service as an individual target in your Xcode project. Each service gets its own sandbox—specifically, it gets its own container and its own set of entitlements. In addition, an XPC service that you include with your app is accessible only by your app. These advantages add up to making XPC the best technology for implementing privilege separation in an OS X app.
XPC is integrated with Grand Central Dispatch (GCD). When you create a connection, you associate it with a dispatch queue on which message traffic executes.
When the app is launched, the system automatically registers each XPC service it finds into the namespace visible to the app. An app establishes a connection with one of its XPC services and sends it messages containing events that the service then handles.
For more on XPC Services, read Creating XPC Services in Daemons and Services Programming Guide. To learn more about App Sandbox, read App Sandbox Design Guide.
Caching API
The
libcache
API is a low-level purgeable caching API. Aggressive caching is an important technique in maximizing app performance. However, when caching demands exceed available memory, the system must free up memory as necessary to handle new demands. Typically, this means paging cached data to and from relatively slow storage devices, sometimes even resulting in systemwide performance degradation. Your app should avoid potential paging overhead by actively managing its data caches, releasing them as soon as it no longer needs the cached data.In the wider system context, your app can also help by creating caches that the operating system can simply purge on a priority basis as memory pressure necessitates. The
libcache
library and Foundation framework’s NSCache
class help you to create these purgeable caches.For more information about the functions of the
libcache
library, see libcache Reference. For more information about the NSCache
class, see NSCache Class Reference.In-Kernel Video Capture
I/O Video provides a kernel-level C++ programming interface for writing video capture device drivers. I/O Video replaces the QuickTime sequence grabber API as a means of getting video into OS X.
I/O Video consists of the
IOVideoDevice
class on the kernel side (along with various related minor classes) that your driver should subclass, and a user space device interface for communicating with the driver.For more information, see the
IOVideoDevice.h
header file in the Kernel framework.The Kernel
Beneath the appealing, easy-to-use interface of OS X is a rock-solid, UNIX-based foundation that is engineered for stability, reliability, and performance. The kernel environment is built on top of Mach 3.0 and provides high-performance networking facilities and support for multiple, integrated file systems.
The following sections describe some of the key features of the kernel and driver portions of Darwin.
Mach
Mach is at the heart of Darwin because it provides some of the most critical functions of the operating system. Much of what Mach provides is transparent to apps. It manages processor resources such as CPU usage and memory, handles scheduling, enforces memory protection, and implements a messaging-centered infrastructure for untyped interprocess communication, both local and remote. Mach provides the following important advantages to Mac computing:
- Protected memory. The stability of an operating system should not depend on all executing apps being good citizens. Even a well-behaved process can accidentally write data into the address space of the system or another process, which can result in the loss or corruption of data or even precipitate system crashes. Mach ensures that an app cannot write in another app’s memory or in the operating system’s memory. By walling off apps from each other and from system processes, Mach makes it virtually impossible for a single poorly behaved app to damage the rest of the system. Best of all, if an app crashes as the result of its own misbehavior, the crash affects only that app and not the rest of the system.
- Preemptive multitasking. With Mach, processes share the CPU efficiently. Mach watches over the computer’s processor, prioritizing tasks, making sure activity levels are at the maximum, and ensuring that every task gets the resources it needs. It uses certain criteria to decide how important a task is and therefore how much time to allocate to it before giving another task its turn. Your process is not dependent on another process yielding its processing time.
- Advanced virtual memory. In OS X, virtual memory is “on” all the time. The Mach virtual memory system gives each process its own private virtual address space. For 64-bit apps, the theoretical maximum is approximately 18 exabytes, or 18 billion billion bytes. Mach maintains address maps that control the translation of a task’s virtual addresses into physical memory. Typically only a portion of the data or code contained in a task’s virtual address space resides in physical memory at any given time. As pages are needed, they are loaded into physical memory from storage. Mach augments these semantics with the abstraction of memory objects. Named memory objects enable one task (at a sufficiently low level) to map a range of memory, unmap it, and send it to another task. This capability is essential for implementing separate execution environments on the same system.
- Real-time support. This feature guarantees low-latency access to processor resources for time-sensitive media apps.
Mach also enables cooperative multitasking, preemptive threading, and cooperative threading.
64-Bit Kernel
As of v10.8, OS X requires a Mac that uses the 64-bit kernel. A 64-bit kernel provides several benefits:
- The kernel can support large memory configurations more efficiently.
- The maximum size of the buffer cache is increased, potentially improving I/O performance.
- Performance is improved when working with specialized networking hardware that emulates memory mapping across a wire or with multiple video cards containing over 2 GB of video RAM.
Because a 64-bit kernel does not support 32-bit drivers and kernel extensions (KEXTs), those items must be built for 64-bit. Fortunately, for most drivers and KEXTs, building for a 64-bit kernel is usually not as difficult as you might think. For the most part, transitioning a driver or KEXT to be 64-bit capable is just like transitioning any other piece of code. For details about how to make the transition, including what things to check for in your code, see 64-Bit Transition Guide.
Device-Driver Support
Darwin offers an object-oriented framework for developing device drivers called the I/O Kit framework. This framework facilitates the creation of drivers for OS X and provides much of the infrastructure that they need. Written in a restricted subset of C++ and designed to support a range of device families, the I/O Kit is both modular and extensible.
Device drivers created with the I/O Kit acquire several important features:
- True plug and play
- Dynamic device management (“hot plugging”)
- Power management (for both desktops and portables)
If your device conforms to standard specifications—such as those for mice, keyboards, audio input devices, modern MIDI devices, and so on—it should just work when you plug it in. If your device doesn’t conform to a published standard, you can use the I/O Kit resources to create a custom driver to meet your needs. Devices such as AGP cards, PCI and PCIe cards, scanners, and printers usually require custom drivers or other support software in order to work with OS X.
For information on creating device drivers, see IOKit Device Driver Design Guidelines.
Network Kernel Extensions
Darwin allows kernel developers to add networking capabilities to the operating system by creating network kernel extensions (NKEs). The NKE facility allows you to create networking modules and even entire protocol stacks that can be dynamically loaded into the kernel and unloaded from it. NKEs also make it possible to configure protocol stacks automatically.
NKE modules have built-in capabilities for monitoring and modifying network traffic. At the cellspacing='0' cellpadding='5'>Table 6-1 Network protocols
Protocol
Description
802.1x
802.1x is a protocol for implementing port-based network access over wired or wireless LANs. It supports a wide range of authentication methods, including TLS, TTLS, LEAP, MDS, and PEAP (MSCHAPv2, MD5, GTC).
DHCP and BOOTP
The Dynamic Host Configuration Protocol and the Bootstrap Protocol automate the assignment of IP addresses in a particular network.
DNS
Domain Name Services is the standard Internet service for mapping host names to IP addresses.
FTP and SFTP
The File Transfer Protocol and Secure File Transfer Protocol are two standard means of moving files between computers on TCP/IP networks.
HTTP and HTTPS
The Hypertext Transport Protocol is the standard protocol for transferring webpages between a web server and browser. OS X provides support for both the insecure and secure versions of the protocol.
LDAP
The Lightweight Directory Access Protocol lets users locate groups, individuals, and resources such as files and devices in a network, whether on the Internet or on a corporate intranet.
NBP
The Name Binding Protocol is used to bind processes across a network.
NTP
The Network Time Protocol is used for synchronizing client clocks.
PAP
The Printer Access Protocol is used for spooling print jobs and printing to network printers.
PPP
For dial-up (modem) access, OS X includes PPP (Point-to-Point Protocol). PPP support includes TCP/IP as well as the PAP and CHAP authentication protocols.
PPPoE
The Point-to-Point Protocol over Ethernet protocol provides an Ethernet-based dial-up connection for broadband users.
S/MIME
The Secure/Multipurpose Internet Mail Extensions protocol supports encryption of email and the attachment of digital signatures to validate email addresses.
SLP
Service Location Protocol is designed for the automatic discovery of resources (servers, fax machines, and so on) on an IP network.
SOAP
The Simple Object Access Protocol is a lightweight protocol for exchanging encapsulated messages over the web or other networks.
SSH
The Secure Shell protocol is a safe way to perform a remote login to another computer. Session information is encrypted to prevent unauthorized access of data.
TCP/IP and UDP/IP
OS X provides two transmission-layer protocols, TCP (Transmission Control Protocol) and UDP (User Datagram Protocol), to work with the network-layer Internet Protocol (IP). (OS X includes support for IPv6 and IPSec.)
XML-RPC
XML-RPC is a protocol for sending remote procedure calls using XML over the web.
OS X also implements a number of file-sharing protocols; see Table 6-4 for a summary of these protocols.
Network Technologies
OS X supports the network technologies listed in Table 6-2.
Technology | Description |
---|---|
Ethernet 10/100Base-T | For the Ethernet ports built into every new Macintosh. |
Ethernet 1000Base-T | Also known as Gigabit Ethernet. For data transmission over fiber-optic cable and standardized copper wiring. |
Jumbo Frame | This Ethernet format uses 9 KB frames for interserver links rather than the standard 1.5 KB frame. Jumbo Frame decreases network overhead and increases the flow of server-to-server and server-to-app data. |
Serial | Supports modem and ISDN capabilities. |
Wireless | Supports the 802.11b, 802.11g, 80211n, and 802.11ac wireless network technologies using AirPort Extreme and AirPort Express. |
IP Routing/RIP | IP routing provides routing services for small networks. It uses Routing Information Protocol (RIP) in its implementation. |
Multihoming | Enables a computer host to be physically connected to multiple data links that can be on the same or different networks. |
IP aliasing | Allows a network administrator to assign multiple IP addresses to a single network interface. |
Zero-configuration networking | See Bonjour. |
NetBoot | Allows computers to share a single System folder, which is installed on a centralized server that the system administrator controls. Users store their data in home directories on the server and have access to a common Applications folder, both of which are also commonly installed on the server. |
Personal web sharing | Allows users to share information with other users on an intranet, no matter what type of computer or browser they are using. The Apache web server is integrated as the system’s HTTP service. |
Network Diagnostics
Network diagnostics is a way of helping the user solve network problems. Although modern networks are generally reliable, there are still times when network services may fail. Sometimes the cause of the failure is beyond the ability of the desktop user to fix, but sometimes the problem is in the way the user’s computer is configured. The network diagnostics feature provides a diagnostic app to help the user locate problems and correct them.
If your app encounters a network error, you can use the diagnostic interfaces of
CFNetwork
to launch the diagnostic app and attempt to solve the problem interactively. You can also choose to report diagnostic problems to the user without attempting to solve them. For more information on using this feature, see Using Network Diagnostics.
File-System Support
The file-system component of Darwin is based on extensions to BSD and an enhanced Virtual File System (VFS) design. The file-system component includes the following features:
- Permissions on removable media. This feature is based on a globally unique ID registered for each connected removable device (including USB and FireWire devices) in the system. Business. the game. mac os.
- Access control lists, which support fine-grained access to file-system objects.
- URL-based volume mounts, which enable users (via a Finder command) to mount such things as AppleShare and web servers
- Unified buffer cache, which consolidates the buffer cache with the virtual-memory cache
- Long filenames (255 characters or 755 bytes, based on UTF-8)
- Support for hiding filename extensions on a per-file basis
- Journaling of all file-system types to aid in data recovery after a crash
Because of its multiple app environments and the various kinds of devices it supports, OS X handles file data in many standard volume formats. Table 6-3 lists the supported formats.
Volume format | Description |
---|---|
Mac OS Extended Format | Also called HFS (hierarchical file system) Plus, or HFS+. This is the default root and booting volume format in OS X. This extended version of HFS optimizes the storage capacity of large hard disks by decreasing the minimum size of a single file. |
Mac OS Standard Format | Also called hierarchical file system, or HFS. This is the legacy volume format in Mac OS systems prior to Mac OS 8.1. HFS (like HFS+) stores resources and data in separate forks of a file and makes use of various file attributes, including type and creator codes. |
UDF | Universal Disk Format, used for hard drives and optical disks, including most types of CDs and DVDs. OS X supports reading UDF revisions 1.02 through 2.60 on both block devices and most optical media, and it supports writing to block devices and to DVD-RW and DVD+RW media using UDF 2.00 through 2.50 (except for mirrored metadata partitions in 2.50). You can find the UDF specification at http://www.osta.org. |
ISO 9660 | The standard format for CD-ROM volumes. |
NTFS | The NT File System, used by Windows computers. OS X can read NTFS-formatted volumes but cannot write to them. |
UFS | UNIX File System, a flat (that is, single-fork) disk volume format, based on the BSD FFS (Fast File System), that is similar to the standard volume format of most UNIX operating systems; it supports POSIX file-system semantics, which are important for many server applications. Although UFS is supported in OS X, its use is discouraged. |
MS-DOS (FAT) | The FAT file system is used by many Windows computers, digital cameras, video cameras, SD and SDHC memory cards, and other digital devices. OS X can read and write FAT-formatted volumes. |
ExFAT | The ExFAT file system is an extension of the FAT file system, and is also used on Windows computers, some digital cameras and video cameras, SDXC memory cards, and other digital devices. OS X can read and write ExFAT-formatted volumes. |
HFS+ volumes support aliases, symbolic links, and hard links, whereas UFS volumes support symbolic links and hard links but not aliases. Although an alias and a symbolic link are both lightweight references to a file or directory elsewhere in the file system, they are semantically different in significant ways. For more information, see Aliases and Symbolic Links in File System Overview.
Note: OS X does not support stacking in its file-system design.
Because OS X is intended to be deployed in heterogeneous networks, it also supports several network file-sharing protocols. Table 6-4 lists these protocols.
File protocol | Description |
---|---|
AFP | Apple Filing Protocol, the principal file-sharing protocol in Mac OS 9 systems (available only over TCP/IP transport). |
NFS | Network File System, the dominant file-sharing protocol in the UNIX world. |
WebDAV | Web-based Distributed Authoring and Versioning, an HTTP extension that allows collaborative file management on the web. |
SMB/CIFS | SMB/CIFS, a file-sharing protocol used on Windows and UNIX systems. |
Security
The roots of OS X in the UNIX operating system provide a robust and secure computing environment whose track record extends back many decades. OS X security services are built on top of BSD (Berkeley Software Distribution), an open-source standard. BSD is a form of the UNIX operating system that provides basic security for fundamental services, such as file and network access.
The CommonCrypto library, which is part of
libSystem
, provides raw cryptographic algorithms. It is intended to replace similar OpenSSL interfaces.Note: CDSA (Common Data Security Architecture) and OpenSSL are deprecated and their further use is discouraged. Consider using Security Transforms technology to replace CDSA and CommonCrypto to replace OpenSSL. Security Transforms, which are part of the Security framework, are described in Security Services.
OS X also includes the following security features:
- Adoption of Mandatory Access Control, which provides a fine-grained security architecture for controlling the execution of processes at the kernel level. This feature enables the “sandboxing” of apps, which lets you limit the access of a given app to only those features you designate.
- Support for code signing and installer package signing. This feature lets the system validate apps using a digital signature and warn the user if an app is tampered with.
- Compiler support for fortifying your source code against potential security threats. This support includes options to disallow the execution of code located on the stack or other portions of memory containing data.
- Support for putting unknown files into quarantine. This is especially useful for developers of web browsers or other network-based apps that receive files from unknown sources. The system prevents access to quarantined files unless the user explicitly approves that access.
For an introduction to OS X security features, see Security Overview.
Scripting Support
Darwin includes all of the scripting languages commonly found in UNIX-based operating systems. In addition to the scripting languages associated with command-line shells (such as
bash
and csh
), Darwin also includes support for Perl, Python, Ruby, Ruby on Rails, and others. OS X provides scripting bridges to the Objective-C classes of Cocoa. These bridges let you use Cocoa classes from within your Python and Ruby scripts. For information about using these bridges, see Ruby and Python Programming Topics for Mac.
Threading Support
OS X provides full support for creating multiple preemptive threads of execution inside a single process. Threads let your program perform multiple tasks in parallel. For example, you might create a thread to perform some lengthy calculations in the background while a separate thread responds to user events and updates the windows in your app. Using multiple threads can often lead to significant performance improvements in your app, especially on computers with multiple CPU cores. Multithreaded programming is not without its dangers though. It requires careful coordination to ensure your app’s state does not get corrupted.
All user-level threads in OS X are based on POSIX threads (also known as pthreads). A pthread is a lightweight wrapper around a Mach thread, which is the kernel implementation of a thread. You can use the pthreads API directly or use any of the threading packages offered by Cocoa. Although each threading package offers a different combination of flexibility versus ease-of-use, all packages offer roughly the same performance.
In general, you should try to use Grand Central Dispatch or operation objects to perform work concurrently. However, there might still be situations where you need to create threads explicitly. For more information about threading support and guidelines on how to use threads safely, see Threading Programming Guide.
X11
The X11 windowing system is provided as an optional installation component for the system. This windowing system is used by many UNIX applications to draw windows, controls, and other elements of graphical user interfaces. The OS X implementation of X11 uses the Quartz drawing environment to give X11 windows a native OS X feel. This integration also makes it possible to display X11 windows alongside windows from native apps written in Cocoa.
Software Development Support
The following sections describe some additional features of OS X that affect the software development process.
Binary File Architecture
The underlying architecture of OS X executables was built from the beginning with flexibility in mind. This flexibility became important as Mac computers have transitioned from using PowerPC to Intel CPUs and from supporting only 32-bit apps to 64-bit apps. The following sections provide an overview of the types of architectures you can support in your OS X executables along with other information about the runtime and debugging environments available to you.
Hardware Architectures
![Simple InterceptMissile&TurretBehaviour Demo Mac OS Simple InterceptMissile&TurretBehaviour Demo Mac OS](https://img.itch.zone/aW1hZ2UvMzA2NTA2LzE1MDQzOTIucG5n/original/uKqfXs.png)
When OS X was first introduced, it was built to support a 32-bit PowerPC hardware architecture. With Apple’s transition to Intel-based Mac computers, OS X added initial support for 32-bit Intel hardware architectures. In addition to 32-bit support, OS X v10.4 added some basic support for 64-bit architectures as well and this support was expanded in OS X v10.5. This means that apps and libraries can now support two different architectures:
- 32-bit Intel (
i386
) - 64-bit Intel (
x86_64
)
Although apps can support all of these architectures in a single binary, doing so is not required. The ability to create “universal binaries” that run natively on all supported architectures gives OS X the flexibility it needs for the future.
Supporting multiple architectures requires careful planning and testing of your code for each architecture. There are subtle differences from one architecture to the next that can cause problems if not accounted for in your code. For example, some built-in data types have different sizes in 32-bit and 64-bit architectures. Accounting for these differences is not difficult but requires consideration to avoid coding errors.
Xcode provides integral support for creating apps that support multiple hardware architectures. For information about tools support and creating universal binaries. For information about 64-bit support in OS X, including links to documentation for how to make the transition, see 64-Bit Support.
64-Bit Support
OS X was initially designed to support binary files on computers using a 32-bit architecture. In OS X v10.4, however, support was introduced for compiling, linking, and debugging binaries on a 64-bit architecture. This initial support was limited to code written using C or C++ only. In addition, 64-bit binaries could link against the Accelerate framework and
libSystem.dylib
only. Starting in OS X v10.5, most system libraries and frameworks are 64-bit ready, meaning they can be used in both 32-bit and 64-bit apps. Frameworks built for 64-bit means you can create apps that address extremely large data sets, up to 128 TB on the current Intel-based CPUs. On Intel-based Macintosh computers, some 64-bit apps may even run faster than their 32-bit equivalents because of the availability of extra processor resources in 64-bit mode.
There are a few technologies that have not been ported to 64-bit. Development of 32-bit apps with these APIs is still supported, but if you want to create a 64-bit app, you must use alternative technologies. Among these APIs are the following:
- The entire QuickTime C API (deprecated in OS X v10.9; in a 64-bit app, use AV Foundation instead)
- HIToolbox, Window Manager, and most other user interface APIs (in general, use Cocoa UI classes and other alternatives); see 64-Bit Guide for Carbon Developers for the list of specific APIs and transition paths.
OS X uses the LP64 model that is in use by other 64-bit UNIX systems, which means fewer headaches when porting from other operating systems. For general information on the LP64 model and how to write 64-bit apps, see 64-Bit Transition Guide. For Cocoa-specific transition information, see 64-Bit Transition Guide for Cocoa.
Object File Formats
OS X is capable of loading object files that use several different object-file formats. Mach-O format is the format used for all native OS X app development.
For information about the Mach-O file format, see OS X ABI Mach-O File Format Reference. For additional information about using Mach-O files, see Mach-O Programming Topics.
Debug File Formats
Whenever you debug an executable file, the debugger uses symbol information generated by the compiler to associate user-readable names with the procedure and data address it finds in memory. Normally, this user-readable information is not needed by a running program and is stripped out (or never generated) by the compiler to save space in the resulting binary file. For debugging, however, this information is very important to be able to understand what the program is doing.
OS X supports two different debug file formats for compiled executables: Stabs and DWARF. The Stabs format is present in all versions of OS X and until the introduction of Xcode 2.4 was the default debugging format. Code compiled with Xcode 2.4 and later uses the DWARF debugging format by default. When using the Stabs format, debugging symbols, like other symbols are stored in the symbol table of the executable; see OS X ABI Mach-O File Format Reference. With the DWARF format, debugging symbols are stored either in a specialized segment of the executable or in a separate debug-information file.
For information about the DWARF standard, go to The DWARF Debugging Standard; for information about the Stabs debug file format, see STABS Debug Format. For additional information about Mach-O files and their stored symbols, see Mach-O Programming Topics.
Runtime Environments
Since its first release, OS X has supported several different environments for running apps. The most prominent of these environments is the dynamic link editor (
dyld
) environment, which is also the only environment supported for active development. Most of the other environments provided legacy support during the transition from Mac OS 9 to OS X and are no longer supported for active development. The following sections describe the runtime environments you may encounter in various versions of OS X. dyld Runtime Environment
The
dyld
runtime environment is the native environment in OS X and is used to load, link, and execute Mach-O files. At the heart of this environment is the dyld
dynamic loader program, which handles the loading of a program’s code modules and associated dynamic libraries, resolves any dependencies between those libraries and modules, and begins the execution of the program. Upon loading a program’s code modules, the dynamic loader performs the minimal amount of symbol binding needed to launch your program and get it running. This binding process involves resolving links to external libraries and loading them as their symbols are used. The dynamic loader takes a lazy approach to binding individual symbols, doing so only as they are used by your code. Symbols in your code can be strongly linked or weakly linked. Strongly linked symbols cause the dynamic loader to terminate your program if the library containing the symbol cannot be found or the symbol is not present in the library. Weakly linked symbols terminate your program only if the symbol is not present and an attempt is made to use it.
For more information about the dynamic loader program, see the
dyld
man page. For information about building and working with Mach-O executable files, see Mach-O Programming Topics. Language Support
The tools that come with OS X provide direct support for developing software using the Swift, C, C++, Objective-C, and Objective-C++ languages along with numerous scripting languages. Support for other languages may also be provided by third-party developers. For more information on the key features of Swift and Objective-C, see Development Languages
Copyright © 2004, 2015 Apple Inc. All Rights Reserved. Terms of Use | Privacy Policy | Updated: 2015-09-16
Sprint | |
---|---|
Type | Anti-ballistic missile |
Place of origin | United States |
Service history | |
In service | 1975-1976 |
Production history | |
Manufacturer | Martin Marietta |
Specifications | |
Mass | 7,700 pounds (3,500 kg) |
Length | 26.9 feet (8.20 m) |
Diameter | 53 inches (1.35 m) |
Warhead | W66 nuclear low kt |
Engine |
|
Propellant | Solid fuel |
25 miles (40 km) | |
Flight ceiling | 19 miles (30 km) |
Maximum speed | 12,250 kilometres per hour; 7,610 miles per hour; 3,403 metres per second (Mach 10) |
Guidance system | Radio command guidance |
Silo |
The Sprint was a two-stage, solid-fuelanti-ballistic missile (ABM), armed with a W66enhanced-radiationthermonuclear warhead used by the United States Army. It was designed to intercept incoming reentry vehicles (RV) after they had descended below an altitude of about 60 kilometres (37 miles), where the thickening air stripped away any decoys or radar reflectors and exposed the RV to observation by radar. As the RV would be travelling at about 5 miles (8.0 km) per second, Sprint had to have phenomenal performance to achieve an interception in the few seconds before the RV reached its target.
Sprint accelerated at 100 g, reaching a speed of Mach 10 in 5 seconds. Such a high velocity at relatively low altitudes created skin temperatures up to 6,200 °F (3,430 °C), requiring an ablative shield to dissipate the heat.[1][2] The high temperature caused a plasma to form around the missile, requiring extremely powerful radio signals to reach it for guidance. The missile glowed bright white as it flew.
Sprint was the centerpiece of the Nike-X system, which concentrated on placing bases around large cities to intercept Soviet warheads. The cost of such a system quickly became untenable as the Soviets added more ICBMs to their fleet, and Nike-X was abandoned. In its place came the Sentinel program, which used Sprint as a last-ditch defense against RVs that evaded the much longer-ranged LIM-49 Spartan. Sentinel was itself changed to become the Safeguard Program, which was operational only for a few months from October 1975 to early 1976. Congressional opposition and high costs linked to its questionable economics and efficacy against the then emerging MIRV warheads of the Soviet Union, resulted in a very short operational period.
During the early 1970s, some work was carried out on an improved Sprint II, which was mostly concerned with the guidance systems. These were to be dedicated to the task of protecting the Minuteman missile fields. Further work was cancelled as US ABM policy changed.
History[edit]
Nike Zeus[edit]
The US Army had considered the issue of shooting down theater ballistic missiles of the V-2 missile type as early as the mid-1940s. Early studies suggested their short flight times, on the order of 5 minutes, would make it difficult to detect, track and shoot at these weapons. However, in spite of their much higher performance, intercontinental ballistic missiles' longer flight times and higher trajectories made them, theoretically, much easier to attack.
In 1955 the Army gave Bell Labs, who had developed the earlier Nike missiles, a contract to study the ABM issue. They returned a report saying the concept was within the state of the art, and could be built using modest upgrades to the latest Army surface-to-air missile, the Nike Hercules. The main technological issues would be the need for extremely powerful radars that could detect the incoming ICBM warheads long enough in advance to fire on them, and computers with enough speed to develop tracks for the targets in engagements that lasted seconds.
Bell began development of what became Nike Zeus in 1956, working out of the Nike development center at Redstone Arsenal. The program went fairly smoothly, and the first tests were carried out in the summer of 1959. By 1962 a complete Zeus base had been built on Kwajalein Island and proved very successful over the following year, successfully intercepting test warheads and even low-flying satellites.
New concept[edit]
During the period Zeus was being developed, a number of problems arose that appeared to make it trivially easy to defeat. The simplest was that its 1950s-era mechanical radars could track a limited number of targets, and it could be easily overwhelmed by numbers; a report by the Gaither Committee suggested a salvo of four warheads would have a 90% chance of destroying a Zeus base. This was of little concern during early development when ICBMs were enormously expensive, but as their cost fell and the Soviets claimed to be turning them out 'like sausages', this became a serious problem.
But other issues also became obvious in the late 1950s. One issue was that nuclear explosions in space had been tested in 1958 and found that they blanketed a huge area with radiation that blocked radar signals above about 60 kilometres (37 mi) altitude. By exploding a single warhead above the Zeus sites, the Soviets could block observation of following warheads until they were too close to attack. Another simple measure would be to pack radar reflectors in with the warhead, presenting many false targets on the radar screens that cluttered the displays.
As the problems piled up, the Secretary of DefenseNeil H. McElroy asked ARPA to study the anti-missile concept. ARPA noted that both the radar decoys and high-altitude explosions both stopped working in the thickening lower atmosphere. If one simply waited until the warheads descended below about 60 km, they could be easily picked out on radar again. However, as the warheads would be moving at about 5 miles (8.0 km) per second at this point, they were only seconds from their targets. An extremely high-speed missile would be needed to attack them during this period.
Sprint[edit]
The result of the ARPA study came at the height of the debate over the Zeus system in the early 1960s. The new Secretary of Defense, Robert McNamara, convinced President Kennedy that Zeus was simply not worth deploying. He suggested using the funds allocated to its deployment to develop the ARPA system, which became known as Nike-X, an ad hoc name given by Jack Ruina when he was reporting on the concept.
Nike-X required great improvements in radars, computers, and especially the missile. Zeus had an attack profile lasting about a minute, Nike-X's interceptions would last about five seconds.
Background[edit]
The conical Sprint was stored in and launched from a silo. To make the launch as quick as possible, the cover was blown off the silo by explosive charges; then the missile was ejected by an explosive-driven piston. As the missile cleared the silo, the first stage fired and the missile was tilted toward its target. The first stage was exhausted after only 1.2 seconds, but produced 650,000 pounds-force (2,900 kilonewtons) of thrust. On separation, the spent first stage disintegrated due to aerodynamic forces. The second stage fired within 1 to 2 seconds of launch. Interception at an altitude of one to eighteen miles' altitude (1.5 to 30 km) took at most 15 seconds.
The Sprint was controlled by ground-based radio command guidance, which tracked the incoming reentry vehicles with phased-array radar and guided the missile to its target.
The Sprint was armed with an enhanced radiation nuclear warhead with a yield reportedly of a few kilotons, though the exact number has not been declassified. The warhead was intended to destroy the incoming reentry vehicle primarily by neutron flux.
The first test of the Sprint missile took place at White Sands Missile Range on 17 November 1965.[3]
Design predecessors[edit]
White Sands Missile Range Museum HIBEX rocket display
The 'HIBEX' (HIgh Boost EXperiment) missile is considered to be somewhat of a design predecessor and competitor to the Sprint missile, as it was a similar high-acceleration missile in the early 1960s, with a technological transfer from that program to the Sprint development program occurring.[4] Both were tested at the White Sands Launch Complex 38. Although HIBEX's initial acceleration rate was higher, at near 400 G, its role was to intercept reentry vehicles at a much lower altitude than Sprint, 6100 m, and it is considered to be a last-ditch anti-ballistic missile 'in a similar vein to Sprint'.[1] HIBEX employed a star-grain 'composite modified double-base propellant', known as FDN-80, created from the mixing of ammonium perchlorate, aluminum, and double-base smokeless powder, with zirconium staples (0.125 inches in length) embedded or 'randomly dispersed' throughout the matrix.[5]
The small 'Thunderbird' rocket of 1947 produced an acceleration of 100 G with a polysulfide composite propellant, star-grained cross-section solid rocket motor.[6]
Engines and propellant[edit]
The first stage's Hercules X-265 engine is believed to have contained alternating layers of zirconium 'staples' embedded in nitrocellulose powder, followed by gelatinizing with nitroglycerine, thus forming a higher thrust double-base powder.[7][8]
Testing[edit]
The first test of the Sprint missile took place at White Sands Missile Range on 17 November 1965.[3]
![Simple InterceptMissile&TurretBehaviour Demo Mac OS Simple InterceptMissile&TurretBehaviour Demo Mac OS](https://static.macupdate.com/products/39701/s/diskmaker-x-logo.png?v=1618148695)
Survivors[edit]
Simple Intercept Missile Equation
- The Air Defense Artillery museum at Fort Sill, Oklahoma has both Safeguard missiles (Sprint and Spartan), plus Nike Zeus and HIBEX on exhibit.[9][10][11]
- The White Sands Missile Range Museum has a HIBEX on exhibit.
- Full Scale Replica on Display, RSL#3 Missile Site, Cavalier, ND www.rsl3.com
See also[edit]
References[edit]
- ^ abSprint
- ^Designation-systems Directory of U.S. Military Rockets and Missiles. Martin Marietta Sprint.
- ^ abJames Walker; Lewis Bernstein; Sharon Lang (2005). Seize the High Ground: The U.S. Army in Space and Missile Defense. Government Printing Office. ISBN0160723086.
17 November 1965 First guided SPRINT flight test took place at WSMR
- ^III. HIBEX – UPSTAGE.
- ^UpSTAGE TECHNOLOGY REPORT: SPECIAL MANUFACTURING AND FABRICATION 1972. McDonnell Douglas. p. 162–178, with impact sensitivity on G-24.
- ^'Archived copy'. Archived from the original on 6 August 2002. Retrieved 6 February 2016.CS1 maint: archived copy as title (link)
- ^Up-ship. Sprint missile
- ^DTIC. by SB Moorhead - 1974
- ^http://www.city-data.com/articles/US-Army-Air-Defense-Artillery-Museum-El.html
- ^http://srmsc.org/mis2050.html
- ^ADA park (Fort Sill), photo journal of Daniel DeCristo
Simple Intercept Missile Examples
Bibliography[edit]
- Krips, Jack; Holllngshead, Charles (22–26 September 1975). Ballistic Missile Defense System Guidance Manufacturing Technology(PDF). Missile Manufacturing Technology. Hilton Head Island: National Technical Information Service. pp. 97–132.
External links[edit]
Simple Intercept Missile System
Wikimedia Commons has media related to Sprint missiles. |
Simple Interceptmissile&turretbehaviour Demo Mac Os Downloads
Retrieved from 'https://en.wikipedia.org/w/index.php?title=Sprint_(missile)&oldid=999782915'